Can you clarify what you mean by, "via TikTok"?
Are you getting emails from addresses like Fred@TikTok.com or ....?
I haven't got a clue about how TikTok signup or internals work but usually these days if you sign up for a site using your email address they send you a confirm or activation message for the new account to that email address for you to acknowledge to create the account. You would have received that email. Now, some clever hacker may get around this but an accidental typo wouldn't.