Share the log using the share button on the log page after the server stopped again.
Also, what is the address of the server in question?
Sorry for wasting your time, I have found my issue. Before the crash, I spawned a tnt minecart on my friend as a joke and for some reason, on the 5th or so relaunch of the server, an error report finally appeared. It told me about how the tnt minecart was breaking the server, so I killed it and now my server works again. Lesson learned, no more tnt minecarts.
This was a really fast response and your support team is really great!