PermissionsEx is not working?

I have Pex on my server and the version 1.23.3 because I have a 1.8.8 server but when I go to my server will be displayed in / pl PermissionsEx red and if I write / pex or something in Minecraft then nothing happens in the lastest .log is an error when I restart my server and zwzw:

Your permissions.yml is incorrect.

You should have them checked by a YAML syntax checker.

Thanks PermissionsEx now works again I had a small bug in my permssions.yml and YAML Checker has found it.