128-bit UUID byte swap problem

[kerem]

I'm implementing a custom service with one characteristic and 128-bit UUID.

I am able to set the custom base UUID using sd_ble_uuid_vs_add() but the resulting bytes look swapped in nRF MCP Android application. This is on Softdevice 7.0.0 and SDK 6.1.0.

#define BASE_UUID {0xAB, 0xCD, .., 0x12, 0x34}

the resulting UUID I see is first and last 2 octets swapped, also within themselves like this;

{0x34, 0x12, .., 0xCD, 0xAB}

All the octets in between these 4 are fine.

Any idea what could cause this behavior?

EDIT Attaching screenshot from Android MCP:

[kerem]

I haven't tried any other example but I lookup up other questions here and implemented as seen here setting up the base first and using returned uuid_type from the function sd_ble_uuid_vs_add. I attached a screenshot of what I see on MCP application. Edited my post as this is related to softdevice 7.0.0 and SDK 6.1.0 on nrf51-DK, I'm doing this using Keil 5.0 running inside VirtualBox on OS X.