Account suspended - once again

I'm getting really annoyed with these messages and suspensions. Was there ever a month in which I did not pay my account over the past 21 Years with MTN ? My services on 5 numbers are now suspended. Can this please be rectified ? What can I do from my side to prvent this from happening as all my numbers are fixed contracts ?

Due to the expensive devices charges, there is not much I can do to reach the credit limit below - which is for 6 devices. Now my devices are suspended, and I cannot even phone MTN for assistance

"Yello, this is a reminder that you have exceeded your Credit Limit of R 2870.00 Your services have now been suspended for outgoing calls. Kind Regards, MTNSA"