i was previously using Essentials Chat and PEX at the same time which worked fine apart from that we wasn't able to use /nick to change our names in the chat but would change them in the tab list, i then switched to ChatManager and PEX which allows /nick in the chat and tab list but seems to be stopping PEX from adding the group prefix before our names, Is there a way to fix this issue?

PermissionsEX > config.yml : http://pastebin.com/ahhRwb1Y
PermissionsEX > permissions.yml : http://pastebin.com/Rztvjxzd
ChatManager > config.yml : http://pastebin.com/Bbgqceya

we have more groups but they are all layed out the exact same just different perms so im sure if one works the rest would too.

Any help is greatly appreciated <3

ChatManager is not supported by PEX. You will need a different chat management plugin such as EssentialsChat or EssentialsXChat (both of which also require Vault).

As for the /nick command not working, use Debug Mode and I'm pretty sure you'll see why it's not working. If you don't understand the output you get from Debug Mode, copy the output to Pastebin and post the link in this thread and I'll take a look.

Also, post your full permissions.yml file. Posting a tiny fragment of it doesn't let me see what errors there may be or where inheritances are going wrong and causing problems. If you're unnecessarily paranoid about someone stealing your permissions.yml from Pastebin and copying your server, trust me when I say there's not likely anything you're doing that hasn't been done before and you can also set the Paste to expire in a week, etc. if you must.

once i switched back to EssentialsChat it worked , i dont know how but it did lol sorry for time wasting but thanks for your help :)

You're welcome. :)