Hi there, if you're talking about the NPCs like Patrigio, Bhakam, etc. in West Valencia (Barhan GateWay). They are 'talking' all same using the texts (Bhakam doesn't have one) but, if you go to Volve she says different things but has the same context with what's written on the text. I have music on, just to be sure that my character is still fighting.
You can also check your settings (Audio) if the Dialogue is on.
If you feel that there really is something wrong with your account. It is much better to contact their support team rather than waiting here.