CoAP on BC92: AT-Commands not working

Hello all! I want to send some data over NB-IoT network via CoAP protocoll with the BC92-TE-B evalboard. The Network connection seems fine and I have an IP address assigned. I am using the CoAP AppNote by Quectel

The problem: For the CoAP configuration, it seems that none of the CoAP-related AT commands work. Everytime I enter a CoAP-AT-Command, “+CME ERROR: invalid command line” is returned (same return-value like any other arbitrary string).

*+CME ERROR: invalid command line*
*+CME ERROR: invalid command line*

Firmware version is BC92RBR01A05.

Can anybody help?

Check whether other AT commands can be used. If they fail, they are not supported, or the current firmware version does not support it