Comment by WorldMaker

It might not even be an actual account. Tiktok does the LinkedIn and Facebook "growth hack" thing of pushing users to let it slurp their entire address book on their phones. One of the reasons that it "requires" a phone number is to do address book graphing. Tiktok will send the emails it collects "Hey, your friend X is on Tiktok" to try to drive more accounts. All it takes is one friend/acquaintance to click yes on "Allow Access to Contacts" and your email address is considered fair to spam "on behalf of" your friends.

Social media was a mistake.