Cant open Add-In from local host

Hello all,

I recently created an Add-In using Node.Js & Yeoman according to the documentation provided by Microsoft. "Build your first Word task pane add-in - Office Add-ins | Microsoft Learn"

The Add-In ran fine on my machine and is pretty simple with mostly HTML elements.

I then uploaded the XML-File in the Microsoft Admin Center to distribute it to users.

Eventhough the Add-In Shows up in their Taskbar, it can not be opened and displays the following Error: "We can't open this add-in from localhost - Office | Microsoft Learn"

I tried the fix from the documentation and nothing changed, which is why I think I missed a step.

I would be grateful, if someone could help me/ point me in the right direction as to what steps I am missing.

Thank you in Advance,

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