Controlling settings, permissions, and membership within Teams and channels
Hi, Lloyd,
My name is Didi. I'm happy to help you today.
Sorry to hear you're experiencing this issue. This also happens to me when I try to add guests to my team. It eventually works after multiple attempts.
Could you please check though if the issue also occurs in the web app? On your desktop, please sign in to https://teams.microsoft.com/ using Chrome or Edge browser and see if there's any difference.
You could also go to the Azure Active Directory, add the guest then add them to a group. Please refer to the documentation for the procedure.
https://docs.microsoft.com/en-us/azure/active-d...
Best regards,