Why do some message requests go straight to my normal inbox on TikTok?

So I’m growing quite a bit on TikTok and don’t like to respond to messages of people I don’t know that much (there are a lot of weird people). Normally all the message requests go to “requests” if I don’t follow them and that way I can choose to accept it or not. But some times, the messages just appear in my normal inbox. Even though I’m not following them and have never spoken to them before.

I find this really annoying since I don’t want them to see I opened the message and I don’t even want to respond. But it’s under all the chats I have with my friends so I automatically see it and open it. Why is this the case? It’s only a small amount of messages that come through like that but it confuses me.

Can I do something about this?