Remove Label in Outlook

Hello everybody,

We currently have the following problem that if we set a label in Outlook and this is then removed again. It is still visible to the recipient of the mail. But the sender sees no label when sending the mail.

Microsoft Support has unfortunately not been able to help me for a month.

I hope that someone can help me here.

Greeting
Oli

P.S. If you need more information I can provide you with pleasure.