Sandbox email address shows as wrong address

ope! I'm having this issue. I know this is old but did you ever figure this out?

Does it look like anybody’s interested in what some of us are experiencing… I’m noticing the same thing today.

Re: <<I have created a sandbox account, verified it and added it onto my phone correctly.

I then click into that sandbox account (clicking manage) and I can see the subscriptions I want to test on my app.

If I then go to make any change, it prompts me to input my password which is fine, but the email address is now showing as my personal apple ID and not the sandbox email address.

If I go into the app and try to make the same subscription change, the same prompt appears with the password input, but this time the email address is showing the correct sandbox address that I created.

Why is my personal apple Is showing in the sandbox manage settings? It is causing issues when testing.>>