Powershell: Unable to update PowerShellGet , error: The version '1.4.7' of module 'PackageManagement' is currently in use

I was able to fix this by running the command below in an admin PowerShell:

Update-Module -Name PowerShellGet -RequiredVersion 2.2.5

Hope this helps others!
Source: https://github.com/PowerShell/PowerShellGetv2/issues/599

I don't have the rep to post a comment, but James Graham's post suggesting using the Update-Module worked for me too. Exact same issue, with the exact same version numbers, almost a year later. Yet, I just checked and there's now a 3.0.12 beta available which requires the code below:

Install-Module -Name PowerShellGet -AllowPrerelease -Force

I tried for a while to figure out the syntax highlighting but to no avail.