Disable NB-IOT for mangOH yellow

1

We have the problem with our mangOH yellows that they connect in the US in several cases to NB-IOT.

How we can bring a mangOHJ board that is running in the NB-IOT mode back to LTE-M1 or 2G?
We have send the two following commands via Bluetooth to the board.

AT!SELCIOT=2
AT!SELACQ=LTE-M1,GSM,LTE,LTE-NB1

After sending these two commands we have plugged the mangOH off from the power and plug it in again to have a complete restart.
One of the boards has connected to LTE after that.
But we have 5 more boards which does not connect to LTE or GSM after the restart.

Do we need to reset a specific part of the mnagOH to bring it out of the NB-IOT loop?

2

Have you compared the at!band? Between ok and nok modules?

Can it attach to gsm if you force it to gsm by at!selrat

3

Have tested a second one and set the two AT commands.
after that i send reboot now.
The mangOH start up and connected to LTE and send data.

Perhaps the reboot command was the key.