Dollar General

I went in the store to purchase a prepaid Verizon phone. I asked the assistant manager of they had the phones in stock and she showed me that they did. I waited in line I buy the phone, and the cashier told me that she couldn't sell me the phone. I noticed that there were at least 20 different Verizon phones on the shelf along with the refill cards to be sold. I asked to speak to the assistant manager who told me that they had the phones, and the cashier abruptly walked off to go get her. I waited for about 15 minutes and the assistant manager never came out of the back to answer my question about the phone. She displayed very unprofessional conduct. I'm very concerned about this matter, and will not be returning to that store.