CVS Pharmacy Failed to Bill My Prescription Correctly and Won’t Fix Their Mistake

For a prescription costing thousands every month, I have been dealing with CVS Pharmacy; fortunately, I have a group helping with the payments. One month CVS neglected to bill it accurately, though, and after many calls they have not corrected their error. Their customer service has left me to handle this mistake on my own without help. There have been other problems with them as well. Another prescription I have is one that they are now denying after going through endless hoops to have authorized for a year. Though it entails altering my prescription, I am really thinking about switching to another pharmacy.