Hello @Marcel Wagner
Thanks a lot for this additional info given.
For now, I would like to recall some important point for this app reservation package identity concern... So, they are below as well as a couple of articles:
I- If have followed the accurate steps, you may need to update the store listing to reflect the right naming. Also, the note below brought my attention and I wanted to share it.
The Product name you select only applies to the Store listing in the language you're working in. It does not impact the name displayed when a customer installs the app; that name comes from the manifest of the package that gets installed. To avoid confusion, we recommend that each language's package(s) and Store listing use the same name.
-I found the following articles which are similar to your case scenario.
https://learn.microsoft.com/en-us/legal/marketplace/mpa-change-history-may-2022
-Then, There was a legal term update made on May but If you were doing the same process after that month I would say that this article might not apply but here it is...
https://learn.microsoft.com/en-us/legal/marketplace/certification-policies#114011-app-name
Furthermore, I would think that part of your naming syntax described at the beginning, it seems to be like your Azure AD ID but I could be mistaken on this one.
Looking forward to your feedback,
Cheers,
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