Unable to save default settings with /defaultsettings save

[13:23:09] [pool-6-thread-1/ERROR]: An exception occurred while saving the key configuration: java.lang.NullPointerException: null at de.pt400c.defaultsettings.FileUtil.saveKeys(FileUtil.java:936) ~[?:2.2.0] at de.pt400c.defaultsettings.CommandDefaultSettings$2.run(CommandDefaultSettings.java:84) [?:2.2.0] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_51] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_51] at java.lang.Thread.run(Thread.java:745) [?:1.8.0_51] [13:23:09] [pool-6-thread-1/INFO]: [Goshen: §cCouldn't save the key configuration!] [13:23:09] [pool-6-thread-1/ERROR]: An exception occurred while saving the default game options: java.lang.NullPointerException: null at de.pt400c.defaultsettings.FileUtil.saveOptions(FileUtil.java:960) ~[?:2.2.0] at de.pt400c.defaultsettings.CommandDefaultSettings$3.run(CommandDefaultSettings.java:100) [?:2.2.0] at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_51] at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_51] at java.lang.Thread.run(Thread.java:745) [?:1.8.0_51] [13:23:09] [pool-6-thread-1/INFO]: [Goshen: §cCouldn't save the default game options!] [13:23:09] [pool-6-thread-1/INFO]: [Goshen: §aSuccessfully saved the server list] [13:23:09] [pool-6-thread-1/INFO]: [Goshen: §ePlease inspect the log files for further information!] [13:23:09] [Render thread/INFO]: [CHAT] §cCouldn't save the key configuration! [13:23:09] [Render thread/INFO]: [CHAT] §cCouldn't save the default game options! [13:23:09] [Render thread/INFO]: [CHAT] §aSuccessfully saved the server list [13:23:09] [Render thread/INFO]: [CHAT] §ePlease inspect the log files for further information!