You may need to foreclose. Take your documents to a real estate attorney for an opinion.
Actively practicing law in Texas. Inactive licenses in Arizona and Georgia. All answers are general in nature and no attorney/client relationship exists in this forum.
You must do more than file a paper at the courthouse to take back the house you sold by agreement for deed. You must foreclose the buyer's interest in the same way that you would foreclose a mortgage. You should consult an experienced real estate litigator in the county in which the property is located to help you with the foreclosure.
Disclaimer: This answer is provided for informational purposes only, does not constitute legal advice, and does not create an attorney-client relationship. Actual legal advice can only be provided after completing a comprehensive consultation in which all of the relevant facts are discussed and reviewed.