Mbed SX1261MB2BAS configuration

You’re correct. My question is quite unspecific, which is part of the problem. The reason for that is that I have no idea how to pinpoint the cause of the problem any further, as I’m not in the possession of a spectrum analyzer or an oscilloscope. May I ask which analysis tools you use in general to diagnose LoRa connectivity problems?

Will I be able to answer these questions using an RTL-SDR?