Are you being mentioned in a thread that you don't want to take part in?
You can mute conversations on Mastodon:
1. Log in through your server’s website, or some apps also support thread muting
2. Go to one of your posts in the thread you want to mute
3. Click ⋯ and select Mute Conversation
4. If you haven’t posted in the thread, go to a post in the thread where you were mentioned, then select ⋯ and Mute Conversation
If you change your mind, do the same thing but select Unmute Conversation.