Nasty Employees At Dunkin Donuts

I need someone to address what happened with one manager and two employees At Dunkin Donuts. I was treated disrespectfully, and the situation escalated unnecessarily. They used offensive language toward us, including insulting my sister, even though we were only supporting an employee who was doing her job properly. This kind of behavior is unacceptable. I expect a response as soon as possible. You can contact me at 7179059***. No customer should be spoken to in this manner.