Pay-out refusal

I had been alerted by the sender that I could collect my money and arrived at the counter with all the necessary documents and information. To my great surprise , I get told that the money was returned to the sender as my account has been blocked. Account? What account? I have only used this service once before and also only as a recipient. I had no idea I had an account and nobody can tell me how this supposed account got blocked. Also, nobody thought to inform either party that the transaction was cancelled. This service really sucks!