The proprietary %XFSSYNC command synchronizes and stores AT command
configurations to the modem’s non-volatile memory.pti_v1.1.x≥1
Set command
The set command writes user-modified configuration data to the modem's NVM so that the data persists through the power off cycles. When using PTI firmware, this command must be used instead of AT+CFUN=0 to store configuration data to NVM.