No BlueTooth connectivity with my car

[Simon C]

Previously I had a Noika 300 that connected to my Vauxhall Astra GTC without issue. Since switching to this new Xperia M I cannot use the controls on my steering wheel to answer a call in the car nor can I bring up my contact list on my in car screen so that I can make a call. It must be the phone thats at fault as it worked fine with the Nokia so whats wrong with the Xperia pls?