SAP option on phone menu missing

I have just purchased a 60 plate insignia Elite with CD500 navi system which does have Bluetooth and does pair with my phone. I can successfully use hands free and have set up voice activation. I can receive and make phone calls and see all my contacts in the address book.

BUT I can only receive texts but cannot reply to them or send them as this option is missing from the menu despite the manual saying that a CD500 should have it.

Is there an upgrade I need or is there a reason this...

SAP option on phone menu missing