If it's from one user, then make sure in Google Ads conversion settings you select count every conversion
If its a different user then either the conversion is not from Google Ads, or you need to wait 24 hours for it to show up. Google Ads is not live and there is a delay.
Then most likely the Google Ads conversion tracking is installed incorrectly.
Or you are looking at all conversion, which is not the same as conversions.
I recommend you check the conversion actions. Go to top right > gear icon > conversions > check what you have.