Server stops when mining blocks

Hello, I just joined and I got my server all set up to run forge with some mods (about 69 but, they just add items no extra mobs) for minecraft 1.12.2 and I was able to join the world. I was playing by myself and not more then a few minutes in, I tried to mine a block and my server kicked me off and turned off. I turned it back on and got back in world and went on to harvest potatoes instead and was again kicked off. I turned the server on again and got back on for a third time and I just walked around and was kicked once again. I do not know why it is doing this. I included the link to the last log.

https://mclo.gs/qekae0X