Hello @Coralie,
Can you report a problem to the site developers.
When you create a support request, if you move the internet window, the current request closes 
In my case I discovered this because I wanted to drag documents to my desktop in the support request (so I shifted the internet window) and this caused the request to be closed. Problem that I repeated several times to be sure.
Hello @Domino_Day ,
Thank you for your feedback.
We are aware of the issue and plan to address it in a future update.
Have a nice day