### Issue Summary

Can't connect to my calendars using CalDAV and the URL `https://calendar.zoho.eu`

### Steps to Reproduce

1. Tried to connect on multiple devices, on multiple OS's (Android DAVx, Thunderbird, Gnome Calendar, Apple Caneldar).
2. When I try to connect with my email and APP PW (because I have MFA enabled) authentication immediately fails.
3. If I connect to the per calendar CalDAV URL from calendar settings, it works.

Previously I could use `calendar.zoho.eu` and it would allow me to connect to all my calendars. This no longer works, so I have to add them one at a time. The Calendar webGUI, and [instructions](https://www.zoho.com/calendar/help/setup-caldav-sync.html) still say I can use `calendar.zoho.eu` so this should be working.