I've seen this happen quite often.
First, check whether your budget and conversions are too fragmented across multiple ad sets. Also make sure your Pixel and CAPI events are properly configured and deduplicated.
If you're still getting consistent purchases, I'd avoid making frequent edits and look at the 7-day CPA, CPM, frequency and conversion rate before changing the structure.
Sometimes stability and better conversion signals matter more than constantly tweaking the setup.