I've got the same issue. Can't receive SMS either. No issues making outbound calls or texts, and no problem with data. They've sent me a new SIM card this evening, I'm sceptical that's the answer, but they basically haven't got a clue so are clutching at straws.
Nothing works on this website. You can't give negative feedback, computer says no. Any queries go unanswered, computer says no. When they've exhausted their crib sheet of one answer, questions are unanswered. Great prices, AWFUL service.