Hi, for some strange reason, in the Atom GPS kit, M5Stack did not connect the GPS's receive (Rx) signal to the ESP32. In my repo on Github I show how a very simple one wire mod connects the Rx signal and therefore enables sending of serial commands to the GPS. This is necessary if you want to turn of unneeded NMEA sentences.
I inlcude full source code which shows how to issue commands to the GPS to turn off all NMEA sentenes except for GGA and RMC, use TinyGPS++ to parse and format the GPS data, and log it to the SD card. Please note I don't use the M5 object, I directly inlcude all needed libraries.
There are photos showing how to do the hardware mod on the Github Readme file.