Two options to view, 1) SCRA doesn't mean they don't have to pay bills, you can still contact them. See if they want to pay for the car or give it up. 2) If they want to pay, ask for a pay allotment. They can have the funds go straight to you every month.
Especially if your borrower is a Marine, they don't get pay during basic training. It is a lump sum afterward. That could be a cause for the delinquency.
My opinions are not necessarily my employers.
Rules and Regs minus Relationships equals Resentment and Rebellion. John Maxwell