Did switching niches mess up my TikTok algorithm?

Hey everyone 👋

So I’m kind of confused about how my TikTok is behaving lately. I’ve been posting for a while and actually had 3 viral videos back to back when my content focused on Vietnamese culture — stuff like cultural humor, language differences, food, and daily life. It was doing really well. I was consistently getting strong engagement, and my audience seemed to genuinely connect with it.

Then I decided to experiment a bit and started posting American-style trends — basically popular formats that were doing well on the U.S. side of TikTok. But after that switch, my engagement dropped fast. None of those trend videos took off, and my account performance dipped overall.

Now I’ve gone back to my Vietnamese content, thinking it would bounce back — but here’s the weird part: TikTok is still pushing my videos to mostly American audiences instead of Vietnamese or Viet-American viewers who used to engage before. The new videos are flopping, even though I’m using the same format, style, and hashtags that worked when I first went viral.

I’m wondering if:

The algorithm “retrained” itself around the new American-style videos and now thinks my niche changed?

My original audience stopped being shown my content?

Or if I need to let the algorithm “relearn” my old niche over time by consistently posting cultural stuff again?

It’s frustrating because I can literally see TikTok showing my videos to the wrong demographic — they’re not reacting to the jokes or language, and my engagement rate tanks because of it.

Has anyone here successfully switched back to their old niche and recovered their reach? Did you have to make a new account, or did it fix itself after a while? Any tips for “retraining” the algorithm or signaling my true niche again would be super appreciated 🙏