Checkout UI extension not visible on none development store

Shopify Apps
1

I built an app with a checkout UI extension in it, this all works fine on my development store my target (

purchase.checkout.cart-line-item.render-after) have the react that I want displayed, I have now moved my app over to a live store which we are working on building. Now I have the extension set up in the exact same way, I have run npm run deploy, in my partner dashboard I see the version and it is active but when I go to the checkout either via checkout customisation or through viewing the store I see nothing. To simplify and test I changed my extension (wrote in javascript react) to:

import {
reactExtension,
Text,
BlockStack,
useApi,
useCartLineTarget,
} from ‘@shopify/ui-extensions-react/checkout’;

import {
useEffect,
useState
} from ‘react’

export default reactExtension(
‘purchase.checkout.cart-line-item.render-after’,
() => ,
);

function Extension() {
return(

TEST

)}

and still nothing. Does anyone have a fix for this or know the cause?