Hi AoibhinTB,
Thanks for your post and welcome to the forums. It's really great having you on board with us in the Community.
I'm sorry to hear that you are having an issue with outgoing calls since moving your number across to us.
It can sometimes take 24 hours for everything to go through so it's worth turning the device off and back on again so it can force a new connection to the network. As it's passed the 24 hours, if you're still having issues, pop back here and let us know.
Thanks,