MTN is such a USELESS company!!!

I upgraded an existing contract with MTN in November asked for the new billing amount several times from different consultants only for them to debit more than twice that amount in December. I asked for the recordings of those conversations now I’m being sent from pillar to post already spoken with several useless consultants who refuse to do their jobs! How possible is it I can have 2 data plans on one number running simultaneously? It’s daylight *******! I regret ever taking a contract with them.