Very disappointed customer

I had been looking longingly at some bedding and when it went on special i jumped at the chance to order it. Imagine my disappointment when it arrived missing the 2x pillow cases :( I have tried to call but nobody answers, emailed and recieved only automated replies, sent feedback requesting help 2x on the app, was promised someone would call me withing 3 days, and then only heard back from someone after 5 days who just called to ask if I was home so the item could be returned as she said I could send the item back and then just re-purchase it....which i would do but then i will be paying 30% more as the item is no longer on special.the lady promised to help and said she would.cancel the collection and that I could SMS her the issue, and then tonight I see I have an email saying someone tried to collect the item but that nobody was home, but I was here, and also, so not want to return the item, I just want the pillow cases too. Essentially I am terribly disappointed. I was so excited as new bedding is a big treat I havet gotten in many years. Why is it so hard to get this resolved and why can Zando not just send me the missing pillow cases :(