PNA Heathway shocking service

Hi, last week Saturday I went to PNA Heathway to go buy Grade 8 books. I only managed to find 1 book the others were at Greenstone branch according to the sales lady. She said she'll order them for me and they'll arrive latest Wednesday. On Monday I called them to order 2 more books and that sales lady said they do have them but she'll confirm if they are not customer orders and she'll come back to me - that didn't happen. Today when I call them they don't have a clue of what happened to order cos there was no follow up from the sales ladies who took those orders. I asked to speak to the manager I was told he/she's not available but the assistant manager was busy on another call and she'll call me back. I received a call from PNA Heathway after probably an hour, I kept on saying hello but there was no response from the other end and they dropped the call and never bothered to call back. I'm so mad cause that order was urgent they're needed as school...I really cant believe such incompetence.