Conversion values in Google Ads not consistent

So I’m just trying to get ready for GA4 and recently installed this plugin and setup Google Ads Conversion Tracking through GTM.

Everything seemed fine until I checked in the conversion > webpages and notices that about 1 in 5 conversions had a conversion value against them and the others had 0 (even though the default is 1 if there is no conversion value). I have tested in Tag Assistant and can see all data in the data layer so I’m not sure why it’s recording some values but not others. Google Analytics 4 and UA are tracking all conversions and values are normal so I am really not sure what’s causing it.

What would be causing these conversions to have 0 instead of the default 1? Having said that, this is an e-commerce store so all conversions have a value.

I’ve been trying to work it out for a few days now. One thing I noticed after reading this forum is that I have the events setup slightly different (based on a YouTube guide). My “purchase” event is simply “purchase” whereas I see gt4m.orderCompleteEEC – am I using the wrong event and variables? I noticed in Tag Assistant that both events fired but the purchase event was second whereas the gt4m event happened first.

Does anybody have any suggestions on what I could try?

Thanks for any help, I really appreciate it.