Extremely Long Waiting Period for warranty repair

I've had my PC with them since 09 Feb 2015 for a warranty repair as the USB ports and LAN adaptor did not work. They said that the motherboard is the problem and sent it to head office from where it had to go to the supplier apparently. Initially they said that it might take up to 21 Working days. After following up on almost a daily basis after the 21 working days, they didn't come back to me, I had to phone them every time to get an update and then it wasn't proper updates, almost as if they didn't know themselves what the status was. Eventually the status was that they waited for the supplier to confirm if it will be a swap out or credit, this stayed the same for about two weeks, there after the status changed that they are awaiting the back plate of the motherboard and that status also stayed unchanged for another two weeks. Eventually, on the 25th of March, they received my new motherboard back, believe it or not, without a damn back plate! Now the branch is still awaiting the back plate, FOR TWO WEEKS ALREADY!!!!!! This is absolutely ridiculous. Where I asked them from the start that this is for business use, they didn't bother at all to help me! No more Matrix for us at work