Can't change banking details due to bank account that is not older than 3 months. How ridiculous

Good day, I've been trying to change my banking details for the last two weeks. Eventually I got hold of someone today, just to be told that they can't change the banking details seeing that it is not yet 3 months old. So now they will keep on putting through the debit order, that will not go through on the old account seeing that it has been closed, affecting my debit score. They now expect me to do a manual payment every month for the following three months. Have you ever heard of something as ridiculous as this.