I encountered these problems with two identical boards and I managed to make them work only today after more than a week of testing, the strange thing is that I did the same thing the other day and last week and they didn't work and today yes, after having done the factory reset several times yesterday and last week too, putting the credentials back on and they weren't working, but today yes, then the problems encountered were these, an error is the one that does not identify me the communication with the door even if "it works for me" , the other is ERR2 PARSE ERROR, this is an error that pops up on most of the at commands without a valid reason, another is: ERR14 2 UNABLE TO CONNECT Failed to access network and the last one is this : ERR14 5 UNABLE TO CONNECT Failed to login AWS (MQTT) broker, even though I entered the correct credentials and port.
After this last error, I rewrote the at command connect and it connected, then the problem I was having with the quick connect to use the AWS IoT demo was an error code 400 and the terminal shut down saying Thing doesn't exist , this problem was solved precisely after using another terminal which is Hercules SETUP, I did all the resets and put the credentials back and reconnected after trying several times, I would like to understand why two brand new boards have the same problem, searching on the net I saw that there is no explanation regarding these problems encountered, and they have not only software problems but also hardware problems since most of the time the ports are not identified
Thanks