Already did. It happen last week. https://gtm.you1.cn/sharedfiles/filedetails/?id=3127186487

I would go as far as say there is bias going on here. I wouldn't put it passed the person that locked your account because they saw the Chinese alphabet at the end of your profile name and thought you must be a hacker or scammer because we've been led to believe that most hackers or scammers come from China or Russia. I am not saying this is the cause , but it could be one of the possible causes. Valve is a USA company and racism is rife in the USA right now, not to mention Wokeism.

Try and contact support

Ya... that's too harsh. Feeling unfriendly to user when there is no warning before locking up our account instantly.

That is a 15 year suspension, that seems a bit harsh. Contact Steam Support although I don't have much faith they will actually listen to you or your plight.

They gave me a 3 months suspension in 2020 but when I contacted them and said its during covid, I can't see IRL friends and that my interaction with the community was good for my mental health, because I was isolated due to covid they still would not unlock my account.

Did you contact support?