HI @NonpowerApps
Welcome to the Power Pages forum. If you have all the right permissions and still you are getting the above-stated error. It is due to your global admin might have denied portal creations for your org.
Adding official docs below:
https://docs.microsoft.com/en-us/power-apps/maker/portals/control-portal-creation
Your global admin has used PowerShell scripts to stop creating the portal.
To solve this problem:
1. Go to the following URL
2. https://powerapps.microsoft.com/en-nz/developerplan/
3. Click the "Existing user ? add a dev environment" button
4. Sign in using your org.
Please wait for a few minutes and see if a new dev environment is created for you. Then you will be able to create portals in your own environment.
In Incognito window:
1. In new tab signup for a new office 365 trial and get the new id
2. Then open the above-mentioned developer URL and sign up for a dev environment using your new trial id.
NB: Power Pages is the new family member of the power platform. If you are interested in creating power pages then try the below URL
https://make.powerpages.microsoft.com/
Hope it helps.
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