How can I block or unblock a user? Follow
If you have added a user, or they have directly messaged you, you can choose to block them at any time in your chat settings with that user. You can also click on the three dots in the top-right corner of a user's profile to Report or Block.
Once blocked, they will be added to your blacklist, and you will then be unable to receive messages from the user. If you wish to see who you have blocked, or to unblock a user, go to your profile settings and go to “Blacklist”. Here you can manage all the contacts you’ve blocked.