it blocks users by just visiting the profile, with @bevo it happens every time I view one of his posts. I unblock and click his next post and he is blocked again...

Go to the Security Filters and check where us bevo there. If as a block or spam. Are you following bevo? If you don't follow a user and the anti-spam is active (Security filters on the left drawer) and the app sees spam from that user (5+ equal messages), it will block that person.