I had registered my domain on Zoho and created an account: zachan.dev. I was able to login to Zoho using the email address: zach@zachan.dev. I was also able to receive and send emails using POP3 and IMAP after I subscribe to the suitable plan.

However, suddenly, without any operations to the account, I cannot login back in 2 days ago. My Outlook also complains that Authentication Failed, so emails cannot be received anymore. I tried to log back into my Zoho account, but I cannot do so anymore. Could you please check what's happening to the account and help me to recover it, please? I am using this email address for business communications. Thank you!