I can see the config files for the server and we do not appear to be doing anything special. The I'ms arrive in perfectly but never create a new tab.

One thing I did find was

{playerto} : player receivings name

{playerfrom} : player sendings name

tellformatto: '&6You &8-> &f{playerto}&8:&e' tellformatfrom: '&f{playerfrom} &8-> &6You&8:&e'

But not sure if that would have changed anything

Any help would be greatly appreciated.