Be prepared to get billed for repair especially since you’ve opened it:
”Repairing. Your Mac mini doesn’t have any user-serviceable parts. Do not open or disassemble Mac mini or attempt to repair it or replace any components. Disassembling your Mac mini may damage it or may cause injury to you. If your Mac mini needs service, is damaged, malfunctions, or comes in contact with liquid, contact Apple or an Apple-authorized repair center, such as an Apple Authorized Service Provider. If you attempt to open your Mac mini, you risk damaging your computer, and such damage isn’t covered by the limited warranty on your Mac mini.”
Excerpt From
Mac mini Essentials
Apple Inc.
https://books.apple.com/us/book/mac-mini-essentials/id1107061956
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