I may be wrong on this but I don't think the CAA will give out exam results over the phone, only in writing. Your groundschool should receive the results around 2 weeks after you have completed the exams and if you phone them they should be able to tell you.
I never recieved my exam results from the CAA and had to ask them to re-issue them. It was around the time of the postal strikes so I guess Royal Mail 'lost' them. The CAA were very helpful and the results arrived promptly.