I have your Sixfab 3G,4G/LTE shield and EC25 module. I followed your tutorial https://sixfab.com/gps-tracker-with-3g-4glte-shield/ and I have problem. When I write down AT+QGPS=1 in minicom I get “+CME error: 504”. Do you know why? Besides I don’t see what I typing in minicom (like typing of a password).
Which other ports should be tested. I am also having similar problems now (it was working before). The USB2 device is interacting properly, but I get the 504 error when I attempt to activate the feed. If I issue
I get this
+CME ERROR: 501