Server stops during start up in StoneBlock 2

Me and my friend were trying to set up his server with the modpack StoneBlock 2 from FTB and so far the server eithers stops before going online, or in one case became online and about 10-15 seconds later stoped on it's own again.

Since this was a fresh install we don't know what the issue could be, the latest server log is this one : https://mclo.gs/0zcHAKZ

For now i'll try to start it until it works and i'll update the thread if i see any new information in the server logs.

Any help is apreciated, thanks in advance .

The server was stopping on it's own so its not about our client's version of forge, it seems that this modpack for some reason sometimes works and other times it doesn't. Since i made the post the server has managed to stay up at least 2 times.

Right now we were trying to start it to go play a bit but it failed to start twice in a row already. So if anyone is also having a similar issue just keep trying because it seems like it eventually works.