Dollar General review: rude employee

My sister recently visited Dollar General in Bay Springs, Ms. in order to make a purchase
for my mom who has dementia and is bedridden. She presented a check to the cashier and she was told very rudely that the check was declined. My sister knew that the check was good but went to the bank to make sure. The lady at the bank said the check
was good and it was the system at Dollar General that was messed up. My sister returned to the store and was once again treated very rude so she left and will no longer do business there. This employee needs to be reported!