Bad customer service

On Friday I bought items and paid cash. The chasier gave me less change then what I was supposed to receive. When I checked the slip the amount she said I gave her was less then what I actually gave her.I asked her about my change and she was very rude. She went to call someone to cash her till up. That lady told me that they can't do anything about it or refund me because her till was already short. She took my number and said the manager will contact me the following day. Till now I have not received any calls from him.