AT&T Network Fix Solution
Some of our clients purchased GL-X750(Spitz) or GL-E750(Mudi) with EC25-AFFA module, and cannot use it on AT&T network. Here is a solution for your trying.
Step 1: Enter the AT instruction page and execute the command AT+QPRTPARA=3
Step 2: Confirm the modem version and execute the corresponding instruction For version R05, execute at+qfopen="../../usr/fota_ip_a/update_report.ur",1
For version R07, execute at+qfopen="../../data/fota_ip_a/update_report.ur",1
For EP06, execute at+qfopen="../../data/fota_ip_a/update_report.ur",1
Step 3: Execute AT command AT+CGDCONT=1,"IP","broadband" Then, In modem manual Settings, modify your apn configuration to use broadband and click Apply
Step 4: Restart your router