Some of the product shows “cart error”, same product but in different is fine, and we checked the stock is enough. May I know anyone knows what happened, thanks!
Hi @bbhkg
Welcome to the community.
When you have an issue and are posting to the community, you should give as many details as you can. Saying “cart error” is just not enough. We do not know your store link, your theme, what prodiuct as example, is fine, and what exact product has that error.
So if you can share that info, maybe we can see what the issue is.
Hey @bbhkg, that’s an annoying one because “cart error” tells you nothing useful. Good news is your store does know the real reason, you’ve just got to make it show you.
Go to the product page that’s failing, hit F12 to open Chrome dev tools, click the Network tab, then hit Add to Cart. A request called add.js pops up - click it, look at the Response, and it’ll usually spell out the actual problem (“quantity not available” or similar). Nine times out of ten that one line tells you everything.
Couple of other things worth a look, since you said the stock seems fine:
Check the variant’s Available number in the admin, not On hand. If you’ve got unfulfilled orders sitting there, Shopify’s already set that stock aside - so On hand might say 20 while Available is 0, and the cart’s right to block it.
And when you say the same product works “in different” - if you mean a different market or region, have a look at which location holds the stock for the one that’s failing. If that stock’s sitting at a location that doesn’t serve that market, add to cart falls over even though the units exist.
Last thing I’d ask - did you install a new app or publish a theme change just before this started? Anything that touches the cart (bundles, swatches, currency stuff) is usually the culprit when it only hits some products. Turn the newest one off for five minutes and see if it clears. Worth testing in an incognito window too so an old cached cart isn’t throwing you off.
If you drop the message from that add.js response here, plus your store link and one product that’s playing up, it’ll be way easier to spot.