AT+QBAND Get and Set Mobile Operation Band Error

Hello @herbert.pan-Q I am using the BC660-GL development board. I have been trying to set the Band to 20 .
The AT command goes through successfully but when I query the band again it is still the same


+QBAND: (0-17),(1,2,3,4,5,8,12,13,17,18,1


the chipset is BC660K-GL

I was able to sort it
instead of AT+QBAND=?

I am having trouble with the reporting of our NB-IoT devices
They are sending reports intermittently. The chipset we are using is BC660K-GL
On monitoring the behaviour when the devices eventually send reports, it sends up to 10 reports at a go the goes silent again. What could be causing this?

Yes, if you are querying configuration parameters, please execute AT+QBAND?

What exactly does the report mean and can you provide the corresponding log?