GL-M2 - how to tower lock?

I am following this guide to tower lock: Lock Onto That Cell Tower - GL.iNet on the GL-M2 with RM520 modem.

Executing AT+QSCAN=3,1 returns nothing.

Has anyone successfully performed tower lock on the GL-M2? I couldn’t find any documentation on gl_modem.

I don’t know what -B, AT, sp, SAT options mean in gl_modem.

Don’t use gl modem binary it’s buggy . Use full fledged tool like minicom . You can find details of installing it and using it at this post: