Union Bank of India Mobile Banking authentication failed issue

I have shifted from android to iOS. I have got UBI Mobile Banking deregistered by calling customer care so that i can install on my new iphone.

I am using my bank registered sim as physical sim on given slot.

When i open the app on my iphone then it authenticate itself by sending a sms but it gets failed every time i try.

I have already uninstall/offload/mobile restart/sim insert again etc but still unable to activate it on my iphone.

pls help