After login in to my account at any time I open teams it's recommending me to login my old friends account

Remove your friend’s Microsoft account from the phone’s device-level account store, because signing out and clearing Teams data do not remove identities retained elsewhere on the device.

Android

Since you already cleared Teams data and signed out, do not repeat those steps.

1. Open the phone’s Settings.
2. Go to Accounts, Passwords & accounts, or Users & accounts (the name varies by manufacturer).
3. Select Microsoft, Work account, or the entry showing your friend’s email address.
4. Tap Remove account, and confirm.
5. Restart the phone.
6. Open Teams, select Use another account if prompted, and enter your own account manually.

This is the accepted resolution for the matching Teams-on-Android symptom where old accounts remain on the sign-in screen after app sign-out or data clearing.^1^

If the account is stored in Microsoft Authenticator

Check this only if Microsoft Authenticator is installed and your friend’s account appears there:

1. Open Microsoft Authenticator.
2. Select your friend’s account.
3. Tap the Settings gear.
4. Select Remove account.
5. Restart the phone and test Teams again.

Important: Removing the account prevents that phone from approving sign-in verification for your friend. Ensure your friend has another verification method first.^2^

Do not clear all Authenticator data, because that would remove every account and verification registration in the app.

If this is an iPhone or a managed work account

If the unwanted identity is a work or school account, also check:

• Settings → General → VPN & Device Management for a profile belonging to your friend’s organization.
• Microsoft Intune Company Portal, if installed, for an enrollment tied to that account.

Remove these only if the phone is not supposed to be managed by that organization. Removing management can also remove access to organizational email, apps, Wi-Fi, or VPN settings.^3^

If the account still appears after all device-level entries are removed, use Contact Support from Microsoft Support; account details cannot be changed remotely through the Q&A forum.

References

1. remove blocked from log in screen - Microsoft Q&A
2. How to sign out from Authenticator | Microsoft Support
3. Unable to remove Outlook and Teams from IPhone - Microsoft Q&A