Zoho Mail down?

Zoho Mail down?

Hello,
it's been several hours that Zoho Mail, which I use with a custom domain of mine, is behaving weirdly. Seems it doesn't send emails (they show up in Sent yet do not get delivered), and also have big delays in receiving.
Then I get IMAP error messages in MacOS Mail, iOS Mail, and now it also seems impossible to send emails even from https://mail.zoho.eu/zm/#compose ... a mess!

What's happening and could someone please help?