I had a problem with BofA while in DMP too. I opened a Sams Club card and the kicked me out of they program and I would up with 120 day lates from them because they wanted more money then the CCCS was sending to them. My DMP company basically said it was my fault and BofA said too bad. That was almost 3 years ago.
Funny thing was BofA never called me till after the account was several months late.
I few times while in the DMP, I had to pay discover directly since the way they paid the CCCs, it could be over a week between the time the CCCS makes the payment after they were paid by me.
The best advice I can give someone in DMP is that they werent kidding about you having to be proactive in monioring your statements and not opening up the ams card.
My scores would all be well over 800 if I had done so
1/25/2021: FICO 850 EQ 848 TU 847 EX