2nd Monthly suspension in a row

This is now the 2nd month that all numbers on my business contract have been suspended due to a ridiculously low credit limit. I spent most of the morning trying to get hold of the credit vetting department on ***, and also received ref#: ***<br> <br> How can this be resolved once and for all - for the past more than 10 years paying for 9 contracts with MTN, I have not missed even one monthly payment