Hi there,
I have had similar issues as the above, LMIC-Arduino library used with LoRaWAN MAC Version 1.0.2 selected in device-profile with LoRaWAN Regional Parameters set to A. I have got OTAA disabled and trying purely with ABP.
I have disabled frame-counter validation in the device.
I have confirmed my Network session key and Application session key are correct and endianness is correct. I have also checked the raw payload using the lora-packet node.js library, which is able to create the same MIC as in the packet and is able to correctly decode the bytes using the exact settings as defined in the loraserver device settings page.
I am getting the following error in the loraserver logs:
Dec 28 07:14:00 instance-1 loraserver[668]: time=“2018-12-28T07:14:00Z” level=error msg=“processing uplink frame error” data_base64=QEOxhgCATAABMWfam6pCefXtP5sq error=“get device-session error: device-session does not exist or invalid fcnt or mic”
Decoding this base64 to bytes I get “4043b18600804c00013167da9baa4279f5ed3f9b2a”
Which when plugged into the nodejs lora-packet library with the same settings that loraserver has defined, gives me this:
loraserver gateway logs has given me everything that corroborates with what lora-packet has said.
Can confirm MIC is correct between both and I can confirm the decoded bytes in lora-packet are what was sent across.