Hi there,
So the reason you have high CPM is because of ‘ad fatigue’. This is very common on TikTok. TikTok requires constant creative refreshes. If your creative looks like an ad, and people can tell it’s an ad they will skip to the next video, which is what causes high CPM. The same thing will happen if they have already seen the ad before, they will move on again.
Keep creating fresh content, that looks organic. Chances are your CPM will be much lower.
Also try to use TikTok’s exclude audience feature to remove countries that are driving traffic but not conversions. You can also try out lookalike audiences–this will show your ads to users that could potentially be interested.
TikTok has a lot ad features that I highly recommend exploring. I would also recommending posting reddit communities for more tips.