Failed to send proxy message (err -22)

RE: Failed to send proxy message (err -22)

a.da — Mon, 11 May 2026 01:40:38 GMT

Hi Hieu,

Thank you for creating the Pull Request and for your effort in addressing this issue.
I have two follow-up questions regarding the implementation.

Regarding common/smp_bt.c:
I understand the changes in behavior as follows:
Before: Two separate advertising sets were broadcast ( one for Provisioning/Proxy Service and one for SMP Service ).
After: Only the Provisioning/Proxy Service advertising set is broadcast ( since CONFIG_NCS_SAMPLE_MESH_COMMON_SMP_BT_DEDICATED_ADV_SET is disabled in the Distributor sample ).
I assume that broadcasting two separate sets was originally an intentional design to support Mesh DFU.
While disabling the dedicated set avoids the current issue, is there any functional downside to reducing the number of advertising sets?
Regarding dfu/distributor/Kconfig:
The PR references the newly created common/Kconfig using a relative path: rsource "../../common/Kconfig".
This works correctly when building the sample directly within the NCS directory ( ncs/v3.2.3/nrf/samples/... ).
However, when I copy the sample to an external directory (e.g., using the "Create a new application from sample" feature in VS Code), it results in a build error because the relative path becomes invalid.
Is this behavior intentional?
I would like to know if there is a recommended way to handle this for projects managed outside of the SDK tree.

I apologize if these are basic questions, but I would appreciate your insight.

Best regards,

a.da

RE: Failed to send proxy message (err -22)

Hieu — Mon, 04 May 2026 10:27:32 GMT

Hi a.da,

Thank you for your patience.
I agree that having the application work around a BLE Host issue is not correct. However, a fix isn't available yet and the best I could do as a support engineer is to suggest workarounds.

I have made a Pull Request where the second advertising set is not created: samples: bluetooth: mesh: Add new Kconfig to enable/disable SMP adv by hieuv · Pull Request #28483 · nrfconnect/sdk-nrf.

I hope this is OK for you. If it isn't and you require the BLE Host fix, then I unfortunately cannot comment on when it will be available. Our sales team could give better assistance from that angle.

Best regards,

Hieu

RE: Failed to send proxy message (err -22)

a.da — Wed, 15 Apr 2026 07:06:23 GMT

Hi Hieu,

Thank you for your analysis.

Since this issue occurs out-of-the-box within the official sample programs provided by Nordic, I believe it is inappropriate to expect users to implement workarounds at the application level.
To resolve this issue fundamentally, the fix should be implemented within the NCS (SDK) itself.

Could you please provide a proposal or a patch for an official fix on the NCS side?
I would like to know how Nordic intends to address this behavior as a framework-level improvement.

Best regards,

a.da

RE: Failed to send proxy message (err -22)

Hieu — Tue, 14 Apr 2026 12:30:06 GMT

Hi a.da,

My apology for the long waiting time.

We confirmed the issue is that the two advertising sets are started by two different Bluetooth Identity on the same device. However, the phone doesn't know that, and when it connects to the Proxy identity, it tries to use bonding information made with the SMP identity and that fails.

To my understanding, you are evaluating the samples right now. Could you go forward in your project with one of these two options?

Ensure the bonding is made with the Proxy identity
Change the SMP advertising set setup to prevent user from falling into this scenario.

Best regards,

Hieu

RE: Failed to send proxy message (err -22)

Hieu — Thu, 19 Mar 2026 13:07:37 GMT

Hi a.da,

We reproduced your issue.The device is advertising two advertising set, and bonding to the SMP one causes issue when the device works as a proxy.
We are looking into some details and I will send another follow-up soon.

Best regards,

Hieu

RE: Failed to send proxy message (err -22)

a.da — Wed, 18 Mar 2026 04:49:13 GMT

Hi Hieu,

I appreciate your ongoing cooperation.

I re-ran the tests on both iOS and Android, but I could not find the "ATT code 0x1d" log that you pointed out. However, there is something in your log that caught my attention.

your log:

Pairing completed: D0:04:B0:04:3D:3C (public), bonded: 1
[00:05:30.640,720] <wrn> bt_att: Unhandled ATT code 0x1d
Disconnected from SMP service: reason 19 id 1
SMP service advertising restarted
[00:05:59.711,592] <wrn> bt_att: Unhandled ATT code 0x1d
[00:06:01.107,760] <dbg> bt_mesh_cfg_srv: default_ttl_get: net_idx 0x0000 app_idx 0xfffe src 0x0001 len 0:

Did you manually disconnect the SMP Service before operating the nRF Mesh app?
Or was it an unintentional or automatic disconnection?
In my environment, the SMP Service remains connected when the error occurs.
I believe this state is evident from the initial logs I provided.

I look forward to hearing the results from your team’s investigation with an iOS device.

Best regards,

a.da

RE: Failed to send proxy message (err -22)

Hieu — Tue, 17 Mar 2026 19:07:21 GMT

Hi a.da,

This is a little strange. The reason I asked if you reproduced the issue with one or more than one node is because if you are trying to configure the same node as the proxy, then the node shouldn't actually try to send any proxy message. In that case, the error message you see wouldn't match.

I tried with the nRF Mesh (New) app but also couldn't reproduce the issue. I see something strange from the log though:

Connected to SMP service: err 0 id 1
Please enter passkey (508619) on 63:B2:5E:02:8C:22 (random)
Pairing completed: D0:04:B0:04:3D:3C (public), bonded: 1
[00:05:30.640,720] <wrn> bt_att: Unhandled ATT code 0x1d
Disconnected from SMP service: reason 19 id 1
SMP service advertising restarted
[00:05:59.711,592] <wrn> bt_att: Unhandled ATT code 0x1d
[00:06:01.107,760] <dbg> bt_mesh_cfg_srv: default_ttl_get: net_idx 0x0000 app_idx 0xfffe src 0x0001 len 0: 
[00:06:02.097,796] <dbg> bt_mesh_cfg_srv: dev_comp_data_get: net_idx 0x0000 app_idx 0xfffe src 0x0001 len 1: 00
[00:06:02.097,805] <dbg> bt_mesh_cfg_srv: dev_comp_data_get: Preparing Composition data page 0
[00:06:18.343,725] <dbg> bt_mesh_cfg_srv: app_key_add: AppIdx 0x0000 NetIdx 0x0000
Connected to SMP service: err 0 id 1
[00:07:13.288,650] <wrn> bt_att: Unhandled ATT code 0x1d
[00:07:41.422,010] <wrn> bt_att: Unhandled ATT code 0x1d
[00:08:32.419,589] <dbg> bt_mesh_cfg_srv: get_model: ID 0x0002 addr 0x0003
[00:08:32.419,604] <dbg> bt_mesh_cfg_srv: mod_bind: model 0x20001738 key_idx 0x000
[00:08:32.419,612] <dbg> bt_mesh_cfg_srv: mod_bind: model 0x20001738 id 0x0002 i 0 key 0xffff
[00:08:32.419,629] <dbg> bt_mesh_cfg_srv: mod_app_bind: status 0x00
[00:08:40.564,791] <dbg> bt_mesh_cfg_srv: mod_pub_get: elem_addr 0x0003
[00:08:40.564,806] <dbg> bt_mesh_cfg_srv: get_model: ID 0x0002 addr 0x0003

The warning of unhandled ATT code 0x1d is strange. ATT code 0x1D is an BLE Indication operation and I don't expect an indication to happen with this setup.

I will try to ask for get help from someone with an iOS device next.

Best regards,

Hieu

RE: Failed to send proxy message (err -22)

a.da — Tue, 17 Mar 2026 01:59:51 GMT

Hi Hieu, thanks for your reply.

[quote userid="9456" url="~/f/nordic-q-a/127399/failed-to-send-proxy-message-err--22/563376"]I cannot reproduce your issue. I am using an Android device though, so that might affect things.[/quote]

I am using iOS (iPhone Xs Max) and iPadOS (iPad mini 6th), and the issue occurs on both devices.
The version of the nRF Mesh app I am using is 4.7.0.

Regarding Android, I tested with an older device (Android 8.0.0) and found inconsistent results depending on the app:
(I was not aware that there were two different mesh apps for Android as I primarily develop on iOS.)

nRF Mesh app (v3.4.0): The issue did not occur.
nRF Mesh (New) app (v0.9.2): The issue did occur, same as on iOS.

[quote userid="9456" url="~/f/nordic-q-a/127399/failed-to-send-proxy-message-err--22/563376"]Are there any other nodes in your mesh network?[/quote]

There are no other nodes in the mesh network.

Test with two nodes:
I also tested with two nodes in the network and observed the following:

If I perform pairing/authentication with the Proxy Node's SMP Service, the issue occurs.
If I perform pairing/authentication with the Non-Proxy Node's SMP Service, the issue does not occur, and communication remains successful.

[quote userid="9456" url="~/f/nordic-q-a/127399/failed-to-send-proxy-message-err--22/563376"]Do you mean Mesh operations on the other nodes, and not the Distributor node?[/quote]

In step 5, I am performing operations directly on the Distributor node via the nRF Mesh app. Specifically:

Swiping down on the Node Details screen to read the Composition Data.
Sending messages to a Model, such as reading the Fault Status of the Health Server.

Hypothesis:
As a guess, could this be related to address resolution?
I suspect that after pairing authentication, the smartphone's address might be resolved and switched from a Private to a Public address, which might be affecting the Proxy connection state.

Best regards,

a.da

RE: Failed to send proxy message (err -22)

Hieu — Mon, 16 Mar 2026 21:52:15 GMT

Hi a.da,

I cannot reproduce your issue. I am using an Android device though, so that might affect things.

I would like to check still. Are there any other nodes in your mesh network?

During step 5,

[quote user=""]Switch back to the nRF Mesh app and attempt any Mesh communication.[/quote]

Do you mean Mesh operations on the other nodes, and not the Distributor node?

Hieu

RE: Failed to send proxy message (err -22)

Hieu — Sun, 15 Mar 2026 23:56:49 GMT

Hi a.da,

I will try to reproduce this issue and follow-up with you as soon as possible.

Hieu