iPhone calendar crashes with Outlook events

Here is my Calendar problem: When I create an event on my work calendar on Outlook, I invite my iCloud calendar, so my event show on both calendars.

Everything goes fine until I have to edit or delete that event.

If I edit or delete in Outlook, my phone receives the notification by e-mail. I want to open the attachment in the e-mail, then the screen goes black, and then back to home screen. Same thing if I go in the calendar and want to open the event, the calendar crashes (goes black and back to home screen).

When I do the opposite, creating the event in my phone's calendar (invite my work Outlook account), edit, delete the event, I receive notification in my Outlook, everything goes just perfect.

Thanks for your help!