Congrats on the store. Hard to answer this question without more info.
But I can say that the approach you are looking to do of “copy a campaign and relaunch” is a very tactical approach and is probably not going to do much long term. We could sit here and tell you “turn on Wifi connections only” targeting and that will dry up as well.
The campaigns that I’ve worked on with a very similar experience, the thing that fixed their ROAs was to shift away from a one-track strategy and stop looking for a single trick that’s going to fix it all and instead to build a multi-track strategy. That way they aren’t relying on just 1 to 3 campaigns and target audiences but they have multiple eggs in multiple baskets.
I’m not sure how much you are spending but if my math is right you are spending under $100 a day. So it sounds like you are only doing a couple of campaigns or ad sets. You want to have an approach where if you have a couple of campaigns or ads that “dry up” for a couple of days, you have other campaigns in place that are doing really good when the others are doing bad – which that takes a lot more budget on a day to day and I’m not sure how much you are trying to scale this store to.
One of the ad accounts that I manage right now has two main campaigns and sometimes one of the campaigns doesn’t do so well for a couple of days and the other does very well, sometimes we will go a day without a sale on both and then the next day get 15 ROAS.
So you might have messed things up by turning off your ads that weren’t performing well and you could have gotten a 7x ROAs if you had left it on and let Facebook do its thing.