Got the same call today as well, from 3178007400, just stopped receiving calls from another bogus company that never gave a business name and then these started.
got a call from Retrieval Mediation today. Said they'd only send me letters of the loans based upon if I committed for up to 15 days to pay them. Said I owed for 5 accounts, but if I commit, he'd knock out 2 accounts so I'd only owe 3? That sounded weird because you think they'd just give you a settlement amount for them. Sounds fishy and thought it was weird. Doing some research, any help would be nice.