Outlook integration: each reply creates a new item

Hi. I have a board integrated with my Outlook to create an item when a new email is received. I also installed the Emails & Activities app to be able to reply to those emails (like a ticketing system). This all works as expected: the email thread being logged and updated all within one item.

However, each user reply is also creating a new item. In the screenshot you can see the original item selected, which has the full email thread in the Emails & Activities. But it also has two new items, one for each of the users replies:

These items are erroneous. How can I prevent replies from opening new items?