AT+USIO=2 and problem

I was playing with MKRGSM1400 and executed command to enable trace feature, but accidentally I disabled AT command interface on UART and after reading more documentation this configuration is written in non-violated memory :-(, so the modem stop working with arduino library.

What is the way to enable AT command on UART interface back? Any reset? Procedure?

I received reply from U-Blox support.

There is no way to turn off UART trace without having access to USB interface.

@ArduinoMKRGSMdesiners: Please consider to expose solder point for u-blox modem pins 28, 29 and 17 which will allow to recover from this situation.

For current design after execution "AT+USIO=2" modem become useless.