Did you ask them how they arrived at this decision? Perhaps the name brand supply was unreliable?
Alternatively as the pharmacies are often independently owned, it may be a choice by the owner(s). Have you tried another Amcal pharmacy, with a different owner, to see if they too have stopped buying that medication in?
As @Peterchu mentioned; did your doctor require you to take the name brand? Either way, if you are a regular at the pharmacy, and they don’t carry that particular medication, you can ask for them to get it in. The Amcal where we bought all my mother’s medications offered to get stuff in if they didn’t have it on hand for any reason. They even rang a number of suppliers to get a hold of things for us.
If you have trouble with discerning which tablets to take, many pharmacies will put together Webster packs at no charge for you. The one we used for my mother, delivered at no cost once a week, the packs as needed as well as anything else we needed.
Another alternative is a pill box which is covered extensively in another topic. Find a pill box that suits you and pack your pills in according to when you need to take them.
