Organization fonts in Powerpoint for the web failing with sharepoint shell.

Hey all,

I've been following the guide set here https://learn.microsoft.com/en-us/sharepoint/support-for-organization-fonts-in-powerpoint-for-the-web

And everything works until the very last step. I run this:

Set-SPOCustomFontCatalog -FontFolder "C:\Fonts" -LibraryUrl https://kinepolis.sharepoint.com/teams/Kinepolisfonts/Fonts

but I get the same error every time (Just incase, I changed my actual company name with contoso in the example I share here, in my actual powershell I obviously use the correct name/link.)

Any ideas? I can't find anything on google.