I am trying below PS script but information is not cleared in Managed Contact Information (Microsoft 365 Admin Center) for specific user.
Connect to Microsoft Graph
Connect-MgGraph
Get the user by UserPrincipalName
$user = Get-MgUser -UserId $UserPrincipalName
Clear the desired user properties
$user.Department = $null
$user.OfficeLocation = $null
$user.StreetAddress = $null
$user.City = $null
$user.State = $null
$user.Country = $null
$user.PostalCode = $null
$user.MobilePhone = $null
$user.DisplayName = $null
$user.MailNickName = $null
$user.JobTitle = $null
$user.GivenName = $null
$user.BusinessPhones = $null
Update the user with the cleared properties
Update-MgUser -Id $user.Id -UserPrincipalName $user.UserPrincipalName -User $user