Barred from paying my debt

For some strange reason my MTN debit order didn't go through this month and I didn't know because MTN forgot to mention it to me. I only found out because they locked my account. The best part is that they have also barred me from paying the account, every time I try paying my bill from the app it says I'm barred from paying. not sure if I should laugh or cry, since when does a company try the best to make it impossible to make a payment? its a first for me.