Hi,
Im from Planet and we use Zendesk as our supporting software.
Recently, few of our customers reported that are not receiving any reply from our end and only they are receiving the trigger notifications.
I tried testing myself, by adding myself as a requestor. I did not receive any emails that are replied to in the ticket. Though people who were marked in the CC did receive the reply.
Observations -
1. THis is happening with customers who have organisation email
2. I tried with my personal email - I did receive the replies and notifications