@M199 Not to beat what may be a dead horse, but the booking confirmation copy that I receive in my email for a guest who has just booked does not show a telephone number on it. I can only verify the number that shows on their record. Therefore, I think that the response that @Andrea4731 has provided is best.
I have had phone calls or text messages come through from guests that do not originate from the phone number that I have on their record.
@Alison256 How quickly are you changing the quick reply and then using it to send info to your guest? You may want to delay sending for 24 hours to ensure that the update you have entered gets to the "back-end" server that houses the quick reply software. I.e., there may be a programming delay.