Went into Jet to buy something waited in the queue

Went into Jet Highveld Mall to buy me some clothes. Went to queue. Only one cashier working and she is so slow. There was a long queue the lady in front of me started complaining as well as the people at the back of me then I also responded and started complaining, the lady in front of me said this branch is always like this, no customer service. Month end Friday and only one cashier, she has to run up and down with items of customers with no prices ext. The manager can see whats happening as he was busy on the phone where you open new accounts but does nothing. Maybe I can borrow him my glasses to see as it seems he can\t see clearly.The queue was getting longer and longer but the manger can't see or doesn't want to see'wants happening and goes to the back. The lady and myself left the store after waiting 30min in a queue that's not moving. Without buying anything. Left my thing there and left the store. What bad customer service