Moving the goalposts is an informal fallacy in which evidence presented in response to a specific claim is dismissed and some other (often greater) evidence is demanded. That is, after an attempt has been made to score a goal, the goalposts are moved to exclude the attempt. The problem with changing the rules of the game is that the meaning of the result is changed, too.
Sealioning (also sea-lioning and sea lioning) is a type of trolling or harassment that consists of pursuing people with relentless requests for evidence, often tangential or previously addressed, while maintaining a pretense of civility and sincerity (“I’m just trying to have a debate”), and feigning ignorance of the subject matter. It may take the form of “incessant, bad-faith invitations to engage in debate”, and has been likened to a denial-of-service attack targeted at human beings. The term originated with a 2014 strip of the webcomic Wondermark by David Malki, which The Independent called “the most apt description of Twitter you’ll ever see”.