JSON (Load Error)

Hello together

I have a problem with loading JSON.
I’m new to this forum and couldn’t not find any rules how to post. So
please let me know if there exists a post with the rules.

What sort of information do you need to help me?
In the Attachment you find the error message out of rubymine. You also
find the installed gems. I don’t understand why it can’t load the json
since I have it installed.
I’m running on Linux Mint 17.1 Rebecca.

Thank you for any help