Server restarts every time

Hi Guys!

I started a RolePlay server yesterday on a VPS, and it restarts every time... I use ColdPlay GameMode.

When I or other person enters the server, it says: ''The server is restarting...'' and a few seconds later, you must log again.

I have not found a solution for this problem.. Can I have some help?

Thank you, and sorry for my bad English...