I started a submitting test in Helpdesk -> Support: [Ticket #4978] Problem with iPhone synchronization:
This is a test for submitting. And it works. Thereafter I tried to submit my real text. And still it doesn't work.

Hi, I still have this problem.
I have restarted the laptop. I also did a speed test for downloads and uploads, with success. I have no idea what is going wrong? In the meantime, the submission process has been running for more than 10 minutes.

Try to log out and log in again and maybe clear the browser cache.

I tried to upload an answer in Helpdesk -> Support. But the process is frozen.
What's wrong?