My Zoiper account won't register on a cellular network, why is this?

Question

When connected to a WiFi network everything works as required but when i leave the office and i'm on the road on my 3G/4G cellular network the app won't register so i can't make or receive calls. 

I have contacted my cellular provider and they tell me they are not blocking VoIP calls, is there some settings on my mobile that i need to adjust?

Answer 1

Hi

I'm fighting the same problems, where are you from?

Answer 2

Is your PBX being hosted at home and do you have a firewall there?
Make sure data saver is off and you allow background data

Try TCP as well