Have you turned your phone off and back on? if you already have you might have a post porting fault.
Contact Technical Support. You might be experiencing a post porting fault and the carriers have not updated their routing tables.
Typically its only one carrier that can't send to you. Ask your friends which carriers they are on to confirm.
Based on all the troubleshooting steps that have been exhausted, I'm thinking Dolphy007 might be on the money by saying it could be a post porting technical fault and you'd need to speak with Technical Support.
Let us know how you go.