First confirm that you are using the same email address and sign-in method that you originally used. If you signed up with Google, try the same Google account; if you registered with email, use that email flow.
Still stuck?
Check for verification messages, try a private/incognito window to rule out a stale browser session, and make sure cookies or scripts required by the login page are not being blocked.
If the problem continues, contact Tool67 and include the account email and the exact on-screen error. Never send your password.