Hellbanning
Excerpt from https://en.wikipedia.org/wiki/Hellbanning
Hellbanning is a practice used by some online community managers for protecting a community against Internet trolls. The practice involves making a user invisible to all other users. From the hellbanned user's perspective, however, they seem to be participating normally in the community. The purpose of hellbanning is to make it impossible for other users to respond to a particular user by rendering their contributions invisible and thereby enforcing the community best practice of "not feeding trolls." It can be used to prevent trolls or malicious users from creating new accounts to continue trolling (often every type of ban is easy to avoid).
Hellbanning is a practice used by some online community managers for protecting a community against Internet trolls. The practice involves making a user invisible to all other users. From the hellbanned user's perspective, however, they seem to be participating normally in the community. The purpose of hellbanning is to make it impossible for other users to respond to a particular user by rendering their contributions invisible and thereby enforcing the community best practice of "not feeding trolls." It can be used to prevent trolls or malicious users from creating new accounts to continue trolling (often every type of ban is easy to avoid).