Blu Life Mark not ringing.

I have just acquired a Blu Life Mark phone and it does not ring when I get a call.

I have been into settings but cannot find any reference to ring tones.

It is running Lollipop 5.1 and has been checked that it is up to date on OS.

Can anyone tell me how to set the ring tone please?

Sorry I have put Blu Pure XL at top but the Life Mark is not listed there