💁 How to delete a guest user in SharePoint Online ?
Their profile is still displayed, which can cause confusion when users do searches in SharePoint. Sometimes guest users remain active in SharePoint.
If you want to solve this you can get started via this blog.
Here's how to delete a guest account using Azure Active-Directory
Navigate to https://portal.azure.com
Delete the guest user
How can you delete a guest through Office 365 portal?
Thus, you can remove a guest use in SharePoint Online via PowerShell
Connect-SPOService -Url https://yourtenantnamesharepoint.com -Credential $cred
$ExtUser = Get-SPOExternalUser -filter email@example.com
Remove-SPOExternalUser -UniqueIDs @($ExtUser.UniqueId)
More information can be found here: https://docs.microsoft.com/en-us/sharepoint/remove-users