I am trying to use the Digi XBee 3 Cellular LTE-M/NB-IoT module with a valid SIM. The XBee sees the SIM and can read its phone number, ICCID, IMSI, etc, but it doesn't seem to want to connect to a network. I get a cellular signal strength of 69 that does not change, and the Association Indication stays at 22. I am under the impression that there is no additional setup that needs to be done for it to connect, so is there anything I am doing wrong? I am also using it with the XBIB-U-Dev board.