|This assumes a lot of stuff and a new keyboard is really cheap.|
Might try to pry up the key and remove it. You should or might see a post that held the key. Clean it carefully with iso alcohol
or light amount of soap on very little water rag to clean it then wipe again with clear water on rag. Never put water or alcohol on keyboard parts directly and be careful with alcohol.
Might then try a bit of armorall or even endust. Both have silicone in them. Apply to rag and then wipe post. Re-attach key and try.
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