Hi @Lotte Xia
Teams tag is mainly focused on the general issue of Microsoft Teams troubleshooting. According to your description, your question is not in our support scope. Thanks for your understanding and patience.
The following suggestion is for your reference:
To upload an optional package to the Windows Store, you can follow the steps provided in our official documentation.
Ref: https://learn.microsoft.com/en-us/windows/apps/publish/?tabs=individual%2Cmsix-pwa-getting-started
If you encounter problems while adding the app, our official documentation also provides solutions to MSIX app submission errors.
If you need further assistance, a support ticket can be raised from here.
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