Struggling to Scale - Looking for Advice

Hello,

Since January my business has been very much up and down. I've tried:

- Everything in CBO

- ABO for testing then graduating winners to CBO

And my most recent test is one CBO campaign with 1 scaling ad set weekly testing ad set with minimum spend. This was working great, the minimum spend ad set was giving me the highest ROAS I'd seen in a while. I turned minimum spend off after 7 days assuming Meta would favour these ads but no, all the money has now gone back to the original scaling CBO campaign (where numbers are dwindling).

I'm currently spending about £100/day on just one CBO campaign. My issue with CBO is that even if ads in ABO or CBO w/ minimum spend perform REALLY good, the second I put these winners into my scaling CBO campaign, Meta completely ignores them.

Could someone please advise me on what I should do? Is it worth just starting from a fresh slate/campaign?

Thanks