By default, Zoho Accounts supports a maximum of 50 concurrent sessions for an account to prevent multiple users from using the same Zoho account. If you have exceeded the maximum concurrent session limit, you won't be able to access your Zoho account until you terminate some of the active sessions.
To clear your active Zoho account sessions:
Go to accounts.zoho.com.
Click Sessions, then Active Sessions.
Select the session you wanted to remove, then click Terminate.
If you're unable to access your account, please contact support@zohoaccounts.com.
If you're sharing your Zoho account with multiple users, we urge you to create a separate account for each user.
Sign out from sessions you no longer need.
When you're signing out, make sure you're manually click "Sign Out" from the profile pane instead of just closing your tab or browser.
Keep track of your active sessions at Zoho Accounts (Sessions > Active Sessions).