Error serving Post-Purchase extension

[ThiagoMine]

Hello everyone,

I'm trying to use the Post-purchase extension, replicating the subscription example available at https://shopify.dev/apps/checkout/post-purchase/add-subscription-post-purchase-app-extension, however every time I I try to run the shopify extension serves to perform tests the CLI gives me the following error:

My env file:

SHOPIFY_API_KEY=169575b4***
SHOPIFY_API_SECRET=shpss_***
SHOP=linkerdots-test.myshopify.com
SCOPES=write_products,write_customers,write_draft_orders
EXTENSION_TITLE=UpSell extension
EXTENSION_UUID=dev-d4c037b1-***
PORT=8077
PRODUCT_ID=gid://shopify/Product/6948981932199

My index.js and src/index.jsx are exactly as in the example given in the documentation.