I've had to deal with another MS nonsensical issue when I couldnt install their worthless WMR portal through the MS store. Luckily its possible to run Powershell commands to install it manually.
You can use similar commands to install and uninstall other apps if the MS store misbehaves provided you know the name for those apps.
To install:
Get-AppXPackage *Microsoft.MixedReality.Portal* -AllUsers | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
To Uninstall:
Get-AppxPackage Microsoft.MixedReality.Portal | Remove-AppxPackage