Family Dollar complaint: Horrible Customer And Rude Managment

I Purchased 2 cases of Aquafina water and told the clerk I had a digital coupon for $2 off( $2 off of Pepsi products)
I forgot to put in my number and left but I turned around once I realized my mistake. Went in the store and ask for a return and told the clerk I wanted a refund and purchase the waters again. She went to get the shift manager who has long pink braids and she said it sounds like fraud I have to call the store manager. She called the store manager and she said no because it was 10 mins from closing and it’s to late for returns. She said I had to come back tomorrow even though she could’ve just handled the situation then and there. She basically put me out and said the store is closed it’s 10:00pm and I had to leave. I never in my left felt so disrespected and mistreated as a customer I am “always right”. I even looked up family dollar policy and started reading it to her. Nowhere on the website does it say returns stop at any point. I’m very disappointed and