Assurant/Lowes review: Water heater

Bought a defective water heater/ leaking. Purchased 5yr warrantee with Assurant through Lowes. Lowes took the money at the time of purchase.

Assurant rep requested information for a refund. They are asking for a 22 digit number from the receipt that doesn't appear on my receipt . Lowes says that it a 3rd party and they can't help , but they took the money . Long story short, I want a mailing address to send a copy of my receipt. No more of this back and forth email that isn't getting me anything.