If you sold it, you probably don't own it any more. It all depends on whether title was transferred and the terms of your sale agreement and whether you retained a security interest in the property.
Owing somebody money is NEVER an obstacle to filing bankruptcy. That's WHY they file for protection under the bankruptcy code
Your only proper recourse is to make sure the debt owed to you is properly reported on the debtor's BK schedules. If not, the first and best place to start is to go to the Creditor's Meeting ("341 Hearing") and ask the debtor why your debt was not listed, and ask the Trustee
to request an appropriate amendment to the Schedules to list your claim.
THEN, find out from the BK papers at the court whether you are supposed to file a "proof of claim
" regarding your debt. These are NOT always required, especially if the BK is a "no-asset" case in which you will most likely get nothing if your claim is not secured somehow.
Unsecured creditors are last in line to get paid.
If there was any fraud connected to the loan, you *might* be able to file a lawsuit inside the BK case called an "adversary proceeding" and try to challenge the dischargeability of the debt.
Whether this would be worth the effort depends in part on how many dollars are left unpaid, and how badly to want to collect on it.
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