I Cannot Access My 6 Year Old League of Legends Account

I have been actively playing on my League of Legends account for many years. Last night, I logged into my account without any issues and played my last match at approximately 3:30 AM. However, when I tried to log in again today around 5:00 PM, the system started giving me an error message saying, “The information you entered does not match our records,” and I have been completely unable to access my account ever since.

I have used this account for approximately 6–7 years and invested a significant amount of time and effort into it, so suddenly encountering a problem like this has been extremely upsetting for me. I still have access to the phone number ending in 05* that is connected to the account. In addition, I also purchased approximately 1350 RP on the account about a week ago, which should help verify my ownership and account activity.

I already created a support request through Riot Support, but so far I have not received any response or update regarding the issue.

I request that the security of my account be checked immediately, that all necessary verification and recovery procedures be completed, and that my access to the account be restored as soon as possible. I also ask Riot Games to provide me with a clear response regarding the issue and the current status of my account.