Hi sifus, need some comments about switching to other telco.

I am switching out from U-mobile postpaid to Celcom XPAX postpaid. After 2 months of not paying my bill, U-mobile has barred my usage. I asked the Celcom shop and they claimed just pay for minimum should be able to switch over.

I have paid 1 month to reactivate my U-mobile postpaid just for switching over to Celcom postpaid, the balance 1 month do I still need to clear the payment?

PORT IN UPDATE SMS has stated that U-mobile has rejected my Celcom port in "due to One or more MSISDNs replied NO to SMS Validation." What does it mean?

What shall I do next in order to success changing from U-mobile postpaid to Celcom postpaid?