MTN INCOMPETENCE

It’s the second month now that my MTN debit order has been bouncing “due to insufficient funds” even though I have money in my bank account, I am still waiting for July debit order to go off. They can’t give an explanation as to why.. and I wonder will happen again next month as my credit score keeps sinking because of this company called MTN South Africa. What was once a reputable company has come to this