Testing In-App Purchases on my main Apple ID

Hi there, My Apple ID also is the one I use in App Store Connect. It has "admin" and "account holder" permissions.

I am trying to build an app with in app purchases for the first time. However, whenever I try and go through the in app purchase flow I get an error You are not authorised to make purchases of this InApp in sandbox at this time.".

I have tried making my main apple ID as a sandbox user as well, but it won't let me as it already exists (makes sense).

I have completed all the agreements for Tax and banking and they say active.

What am I missing here?

Thanks in advance

Testing In-App Purchases on my main Apple ID
 
 
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