sharepoint online – Get members of a private channel in Microsoft Teams

Connect-SPOService -Url https://site-admin.sharepoint.com

$privateSites = Get-SPOSite | Where-Object -Property Template -eq "TEAMCHANNEL#0"

Any attempt to get the list of members for a private site returns with Access Denied.

Is there any way to do this in PowerShell?

Not familiar at all with graph API.