After sales service an embarrassment

I have always been a loyal customer and love this brand but this is soon to change. I have purchased a Duffle Bag over a year ago and always had an issue with the zip. This was "fixed" a number of times even during the timeframe my bag was still under warranty. I took the bag back for the same issue and have been advised now that the same process has been followed (tightening the zip slider). I have asked about replacing the zip so that it is fixed properly and permanently this time and was informed that they do not have skilled staff to do this and cannot guarantee quality workmanship. My bag is (now) also out of warranty and cannot be replaced. I am so upset and frustrated with this whole process. I spend a lot of money purchasing this item and now I am forced to use a bag that cannot close properly. What an embarrassment using an original item like that.