[API] Invalid API key or access token (unrecognized login or wrong password)

Retired Boards Appdev Custom Storefronts
1

I am trying to create a checkout using the “/admin/api/2022-04/checkouts.json” end point.

I have successfully gotten a store front access token. Here is the return content for this:
{“storefront_access_token”:{“access_token”:“XXXXXXXXXXXXXXXXX9e34”,“access_scope”:“unauthenticated_read_content,unauthenticated_read_customer_tags,unauthenticated_read_product_tags,unauthenticated_read_product_listings,unauthenticated_write_checkouts,unauthenticated_read_checkouts,unauthenticated_write_customers,unauthenticated_read_customers”,“created_at”:“2022-06-01T14:09:12-04:00”,“id”:61489184921,“admin_graphql_api_id”:“gid://shopify/StorefrontAccessToken/XXXXXXX4921”,“title”:“Phoenix Order Management”}}

I then try to create a checkout using the “access_token” in my test store where the app is installed as a sales channel: https://pdvendortest.myshopify.com/admin/api/2022-04/checkouts.json

I am sending the request with the access_token in the header:
X-Shopify-Storefront-Access-Token:XXXXXXXXXXXXXXXXX9e34

It returns: [API] Invalid API key or access token (unrecognized login or wrong password)

The X-Request-ID is: 649dc97a-e010-42ef-83a8-c9e63d018ee2

Can anyone help me figure out why its not authorizing?