Some analogies (although all may not fit perfectly, but still food for thought)
Can you sue your tuition teacher if your kid fails the exams?
Can you sue the coach of the Indian Cricket Team if India loses to Bangladesh 3-0
Can you book your surgeon if despite him trying his best, your cancer patient dies (there is no negligence) ?
Can you sue the weather department if their forecast is incorrect?
Can you sue your financial advisor if his advice turns otherwise and stock market crashes?
Astrology is a forecast, I would not go into whether it is scientifc or not. I would agree with Mr. Democratic Indian that unless you show either -
1. Gross Negligence in him performing his duties
2. Him endorsing the jewels or horoscope without himself having belief in the matter
I doubt whether it may fall under any ambit of law leave alone CPA.
Astrology is a statistical science and astrologers only give predictions based on statistics collected over a large period of time. One of my relatives is an astrologer and I asked him if hypothetically if someone is born on a space ship, how will you create his horoscope; he told me it is not possible to predict his future because no rules have been set for the same based on statistics.
An important thing to note is that the happening/non-happening of the actual event is not within the control of the astrologer, he merely gives solutions to increase probability in your favour (just as a tuition teacher coaches the kid to improve chances of better results, but it is for the student to write exams properly). So how under any rational law in the world, can he be booked for something which he himself has no control over?
It is a different matter altogether if intentional fraud can be proved.