Account theft

My riot games account was hijacked. A letter came to the post office, they say the Riot Games mail has been changed. Passwords don't work either. I started to peck at tp, I create a ticket, a letter arrives in the mail, here the ticket has been created, you can track it using this link. The link is not working, it says "The page you are looking for does not exist". I wrote several times, as a result, more than a day there is no answer. Does anyone know what to do in such a situation?