Closed during operating hours?

Im rather disappointed in the service of matrix in lambton of late. I went to your lambton branch yesterday to pick up a part for a client and your store was already closed 5:45pm as where your website says 6. As such i had to send someone this morning to pick up the part and hes been there since 9am and left at about 9:40am as your store was still closed. The result of this is that my client is displeased and i might lose the sale due to your poor service. Should i lose my client i have a real pinch to approach the service ombud about this. Really shabby of matrix.