Sync not properly working with Spark

Sync not properly working with Spark

Hello. I have an account with 2 different domains in zoho

I normally use spark for the different email accounts I manage and Mac calendar for the calendars.

Issue is as follows:
- Email sync work very well with both zoho accounts, except for the calendar invites.

- When I receive an invitation to a meeting on any of my accounts and I accept it in mail.zoho.com, it properly shows in the calendar .

- BUT when I receive the invitation and accept it in the email client (spark), it just does not appear in the calendar, although the host receives a confirmation of the acceptance. 

Something is happening with the calendar invites acceptance when using spark on zoho accounts. Can you help me with this, pls? I have checked with other email clients and it is the same issue, so it is not Spark.

This only happens with Zoho.com, when I do the same with a gmail account it works well, as well as other corporate accounts in Microsoft Exchange. 

Thank you.