nrf9160 nRF cloud doesn't pair, stuck at CLOUD_EVT_PAIR_REQUEST

[samo4]

Hello,

I have a Thingy91 which was previously successfuly paired to nrf cloud. I deleted the device from nrf cloud and provisioned new certificates from nrf cloud (and uploaded to device). Now the device won't pair.. no error. See part of the log below.

[0m<dbg> nrf_cloud.api_event_handler: NRF_CLOUD_EVT_USER_ASSOCIATION_REQUEST

[0m<inf> asset_tracker: CLOUD_EVT_PAIR_REQUEST

[0m<inf> asset_tracker: Add device to cloud account.

[0m<inf> asset_tracker: Waiting for cloud association...

[0m<dbg> nrf_cloud_transport.nct_mqtt_evt_handler: MQTT_EVT_PUBACK: id = 1 result = 0

I also tried provisioning certificates with my custom prefix (and changing the NRF_CLOUD_CLIENT_ID_PREFIX), but the result is the same.

I'm currently using LTE-M, but I believe the original pairing was done with NbIOT. That being said.. I'm wondering how is NRFCloud able to support NBIOT (UDP?).

[Albrecht Markus Schellenberger]

Thanks a lot!

Could you fire the AT command AT%CMNG=1 and double-check your certificates? It might be useful to delete them all and add the nRF Cloud certificate one more time.

Regards,

Markus

[samo4]

I started deleting the certificates. I succesfully deleted all certificates in slot 16842753, but I have two certificates left from previous testing in slot 4294967293.. and these two refuse to be deleted. Now, when I look at them.. it seems that the two certificates have wrong type.

AT%CMNG=1
%CMNG: 4294967293,10,"0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A0A"
%CMNG: 4294967292,11,"0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B0B"
OK
AT%CMNG=3,4294967293,10
ERROR
AT%CMNG=3,4294967293,11
ERROR

After this, the modem started to behave weirdly: I'm using default at_client and now there's always timout when querying the modem.

And if I try with asset_tracker, I get the expected:

asset_tracker: Failed to connect to cloud, error -8
asset_tracker: Ensure device has a valid CA and client certificate

Modem fw version is: 1.3.0

Is there a way to return modem to known good state? Answering my own question:

I uploaded nordic hex file for at_client and still didn't get any reply from modem; then I reapplied the 1.3.0 fw update and again uploaded at_clinet.. now I get response, but I still can't delete the two remaining certificates.