@Daniel Becker ,
As we are mainly responsible for general issue of Microsoft Teams, your question which is more related to script is not in our scope. Thanks for your understanding.
The following script is for your reference. I have tested it in my lab. It works well.
$User = "email@example.com"
$PassWord = ConvertTo-SecureString -String "YourPassword" -AsPlainText -Force
$UserCredential = New-Object -TypeName "System.Management.Automation.PSCredential" -ArgumentList $User, $PassWord
Connect-MicrosoftTeams -Credential $UserCredential -AccountId $User
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