Zoom Error Code 124 means "Invalid Link: You must sign in with the same Zoom account on the web to open this link". It occurs when your Zoom desktop client and web portal are signed into different accounts, or if you are trying to view a local recording file that belongs to another computer user profile.
Follow these steps to resolve the issue:
Match Accounts: Open the Zoom Desktop Client and verify the email address you are logged in with matches the account used on the Zoom Web Portal.
Re-log in: Sign out of both your Zoom desktop client and your web browser, then log back in to refresh the authentication.