Hi, Harriet. I am an independent advisor, trying to help other users in the Community with my experience in Microsoft products. Please note that I am a user like you and don't work directly for Microsoft.
I’m sorry that you are having an issue with the new teams. As a user, I understand this can be very frustrating. I deeply understand the issue has affected your work, rest assured I will try to provide you with a solution.
Do you experience the same when you are logged in on the web version of Teams?
Gopal Chaudhary in the article on https://answers.microsoft.com/thread/ce148031-4c17-40bc-a79e-4450b1830ee1 highlights the following steps to resolving the issue:
" If you run into this issue. Do the following.
- Go into Chrome Settings
- Privacy and Security
- Security
- Manage Certificates
- Trusted Root Certification Authorities
- Here you will likely see two entries for 'DigiCert Global Root G2 '. One can be deleted while the error cannot. Delete the one that you are allowed to.
- Restart PC"
I hope this helps you. Let me know if this contradicts what you need. I remain helpful in answering any more of your questions.
Warm Regards
Femi