How to set 3rd party credentials for the Cellular network? [SOLVED]

cellular_credentials_set does not save the value in configuration flash. It must be in every program that you flash to your Electron that uses a 3rd party SIM.
The confusing part is that it’s written to RAM in the UBLOX module, so it will persist through flashing your own code as long as you don’t power down the Electron entirely. But it’s really not saved and the line should always be present.