Clear my name please

I had a contract backdated to November 2020. And due unforseen circumstances I could not afford to continue paying my contract. The year 2023. I received a payment notice from mbd legal who MTN sold the acc too. At the time I made the necessary arrangements to settle the outstanding amount requested from MBD. 2025 I pulled my credit report from Transunion. Only to find MTN listed me under another 3rd party called DMC legal with same outstanding amount. I immediately made contact with DMC sent through POP that was made to the first 3rd party. I cannot move forward with ventures I had planned for myself because of this. Emailed the MTNs legal department numerous time regarding this matter. They are useless and obviously do not care. They selling settled accounts to 3rd party organization I won't be surprised they've been doing this to a bunch of consumers and debt collection companies