I can't help directly, but I have the same problem as of yesterday. However I also cannot receive texts (SMS) in addition to calls. Something to check there.
I placed a post last night looking for help, but no replies yet. From what I gather from other posts the issue could be a 'split port'. It's not something customer service can deal with and will have to be 'escalated'. The bad news is this could take a few days.
I'm expecting a call back on my landline from customer service today, and will update my post with any info or solutions I can get.
Welcome to our Community and thanks so much for your first post - sorry that you're having some issues with receiving calls since porting your number over to us. Do you know what happens when someone tries to call you?
I have located your account from here and all is looking to be correct on the surface; can you advise what handset you're using? You may need to change some handset settings to recognise the new number you have ported; it could still be remembering the original number that was assigned to your SIM. This can sometimes impact incoming calls on certain handsets
If you have an iphone please try Settings> Phone> My number