You are making sales. Analytics says you are not.

What the zero actually means

GA4 is free analytics from Google. A 'session' is a visit. A 'key event' or conversion is an action you have marked as important. Revenue is extra: it appears only when the site sends a purchase event that includes an amount.

So zero revenue plus healthy sales usually means the purchase event is missing, the amount is missing, or the event is blocked before it can send. It does not, by itself, mean the shop is failing. It means you cannot trust that screen until you have tested it.

Checks, in the order that saves time

You or your developer can do these. You do not need to understand the whole of GA4.

1. Confirm the sales exist somewhere else. Shop admin, payment provider, inbox. Write down one recent order number and its value. That is your control.
2. Find the thank-you page. Most setups fire the purchase event on the order confirmation page, not on the basket. If that page never loads, or the event is attached to the wrong address, GA4 stays at zero.
3. Watch a test in Realtime. Realtime is the GA4 view of the last few minutes. Place a small real or test order. Open Realtime in GA4 before you start. You should see your visit, then a purchase. If the visit appears and the purchase does not, the event is the fault. If you do not appear at all, the tag is not running: often the cookie banner, covered in the cookie banner guide.
4. Check the value. A purchase with no amount can show as a conversion worth nothing. Ask your developer whether the event sends the order total and the currency.
5. Ask what changed. If the zero started when an agency, a new theme or a new banner went live, ask what they edited in the tracking. A fresh setup often drops the purchase event that the old one sent.

Overseas traffic is a separate issue

A shop can show lots of visits from countries you do not sell to. Some of that is junk, some of it is real people who will never buy. It explains wasted attention. It does not explain a revenue figure of zero if your actual customers are paying. Fix the purchase event first, then decide whether the odd traffic matters.

What you can count while it is broken

Until the test order shows up, judge the ads and the agency on the shop admin, not on GA4. Tell them the screen is untrustworthy, so you will not treat a drop there as a drop in sales. That single sentence prevents a lot of expensive 'fixes' aimed at a measurement fault.