MyChat Client error #0251: you don't have enough rights to delete messages in your private dialogues
Error
Error #0251: you don't have enough rights to delete messages in your private dialogues
Error description
You can't delete a private message in a dialogue with another user because you do not have rights to do so.
Problem Solution
Enable this rule that allows deleting any messages from own private dialogues in Admin Panel, the section "Rights control", "Permission groups", "Private dialogues", "Deleting any messages in private dialogues" for your users group.