Below are some troubleshooting steps and considerations that may help resolve the issue:
- Check Your Account Type and Conversion
• Teams (even the personal version) is part of the Microsoft ecosystem and generally expects you to sign in with a Microsoft account. In some cases, Skype accounts need to be “upgraded” or converted to Microsoft accounts. (Even though older Skype accounts may work for Skype, they might not be fully set up for Teams.)
• Verify that the Skype account you’re trying to use has been converted to a Microsoft account. If you’re not sure, try visiting account.live.com and signing in with your Skype credentials. If prompted to complete conversion steps, follow them.
- Double-Check Your Credentials
• Confirm that you’re entering the correct email/phone number and password combination. Note that some Skype accounts use a different sign‐in ID (for example, an older Skype username instead of an email address).
• If your account is merged with or converted to a Microsoft account, use that email address to sign in.
- Clear Cache and Try Different Methods
• In a web browser, clear your cache and cookies or try using an incognito/private browsing session. Sometimes cached credentials or cookies can cause conflicts.
• Since you have already tried both the Teams app on your Mac and a browser, double-check that you’re not signed in with another account (for example, in a different window or a saved session) that might conflict.
• If possible, sign out of any other Microsoft-related apps and then try logging into Teams again.
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