Click your Start Button, then just type powershell, and on the resulting list, right click PowerShell and select 'Run as Administrator'.
Paste this into PowerShell and press Enter.
Get-AppxPackage -allusers Microsoft.WindowsFeedbackHub | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register "$($_.InstallLocation)\AppXManifest.xml"}
When that command completes, close PowerShell and restart your PC to apply the change.
That process should reinstall the Feedback Hub app.