Stores closing before the time they are supposed to

I got to PEP in Phalaborwa on Palm Street at 16:55. The doors where already closed and they ladies inside were cashing up. There was a man whom I found at the door and they blatantly ignored us. The man left and I continue trying to get their attention as there is a sign on the door that says they close at 17:00. Clearly the had closed earlier. A lady by the name of Elly told me that their cash registers say it 17:00 there for they are closed. You can’t tell me that my phone, my watch and the phone and watch of the man who left are all wrong.