Sad to say, bad customer service is not exclusive to a type of store or stores, but rather, pandemic in the service industry. (Restaurants, bars, phone service as well!) Too many people just don't seem to care anymore. The best way to resolve the problem, is to talk to the manager. Let him or her know that you were dissatisfied with the service. If it isn't resolved to your satisfaction, let them know you are taking your business elsewhere and they have lost a regular/repeat sales with you. Managers are ultimately responsible for the experience you have and want it to be a good one. They can't fix a problem unless they know there is one. OTOH, once in a while, you get a manager who is just as apathetic as their employees.
Sorry your experience was less than pleasant.