Dr. Flanagan prescribed two meds for my dog in a visit through Vetco (at Petco) last April. My dog was taken there for heart worm test which was negative, and for a prescription for Bravecto and for Trifecta Plus. Weeks ago, I ordered these through Walmart, and only the prescription for Bravecto has been approved by this vet. Even though I have the electronically submitted prescriptions, Walmartpetx wil not accept them. I have made numerous calls to Walmart pet pharmacy, and to the number given on the prescriptions.Each time I call ,I amtold that these prescriptions have been approved, yet Walmart says not. I don't know if this is from the vet's end or from the pharmacy's end, but I am frustrated. I thought it would be cheaper and more convenient to go with Vetco, but not so.