In instances where you are experiencing some unexpected behaviour with your calendar and you have already tried our available troubleshooting steps, we will ask that your retrieve the event ID related to the task so that we can have a deep dive into our logs for you.

To find the event ID in gmail, you will need to click into the event you are having issues with and then edit. The ID will we be displayed in the url after https://calendar.google.com/calendar/r/eventedit/ as shown below:

There wouldn't be an event ID in outlook, in order for us to help you troubleshoot here, we would require the start/end time and the summary of the event. Alternatively you can simply take a screenshot including these details in outlook: