You accidentally wandered into ongoing hostilities between Mastodon and the rest of the Fediverse. Mastadon is kinda block happy, and enforce block lists on whoever wants to be able to talk to them. This is the complete antithesis of what the fediverse was designed for, and people get upset.
Honestly, if you were happy on twitter, where people you didn't know decided what you could and couldn't see, stick to Mastadon.
Nice art, BTW.