SIM7600CE connectivity issue with Arcduino Uno

I have set the baud rate to 9600 on my SIM7600CE shield using AT+IPREX=9600 then I rebooted it and now I cannot communicate with it even though I have set my Arduino repeater program to 9600. Is there something else I need to do?
If I cannot get it to talk at all then is there a way of returning the device to factory settings without using the AT command set since I cannot communicate with it?

Interestingly it reverted to 115200 after I left it for a while and then rebooted it(!?!)
I read about its auto baud rate detection. What is the best way to trigger that behaviour? Maybe that is the best way to force it to 9600.