Buyer coming back after months demand for repair cost

[Irfan Saeed]

Hello Bigger Pocket friends - I have an urgent question to ask. I sold a house couple of months ago. Buyer wanted some plumbing repairs done at the property and he send me an amendment for repairs. I had the repairs done and the buyer did a re-inspection and close the property. A month after the closing he send a text message and start complaining about plumbing issues again. I told him that you did the inspection before closing and now I am not responsible for any more work. He did not follow up after that. Now after couple months he send me an email and demand about 3800 worth of plumbing repairs and threatens me to sue. What are my options

Thanks