This is like Scam 101, bro. Even if TikTok were contacting people in this totally asinine way, they would do so from TikTok.com and nowhere else...definitely not a .ml domain or whatever.
Aside from that, social media platforms RARELY contact their users personally if ever, and I've never seen an instance where they contacted users on another platform.
If it sounds too good to be true, it is!