Left out of pocket by Incompetent & Unhelpful Cust. Service

Very disappointed...completely unhelpful Customer Service which falls far below the standards that I had come to expect from Debenhams. It all started when I placed an online order for some Xmas presents paid for with my bank card registered to my home address but with delivery to my parents address where I would be spending Xmas (so I wouldn't have to struggle lugging it across and then out of London) something I have done for the past 10 years. 24 hours later my order was cancelled...without any explanation. Thinking that maybe there was a problem with my card I tried again but used a different bank debit card...again registered to my home address. Again my order was cancelled. So I contacted Customer Service who informed me that all three of my items were out of stock and that's why my orders had been cancelled. I challenged this as they were showing as plenty in stock online. I asked her if she would go and check...it turned out that that only one of the items was out of stock (which I subsequently found was a lie) which is why my orders had been cancelled. She re-did my order for me for the two items that were in stock. £6.50 worth of telephone call later and I thought that was it all sorted...but Oh No...I received another email today, (24 hours after placing my order over the phone) to say my order had been cancelled...again with no explanation. So yet again another lengthy and costly call to Debenhams Customer Services!!!! I was told it was because there was a problem with my bank card... until I informed her that I had tried two different cards for two different banks with the same end result. She then told me that I cannot have my order delivered to an address that is different from my billing address which I knew to be incorrect. I was then told the only thing I could do was reorder and collect from a local store...which defeats the whole point of me arranging delivery. So I asked, perhaps I could order for collection at a Debenhams closer to my parents but I was told that they would only hold my items for 14 days and I would have to pay in store...not much use when I am not travelling to my parents until 23rd December!!!! When I gave them my parent’s postcode for them to tell me where the closest store to my parent is then told me Gateshead...which is over 400 miles away from where my parents lived. Clearly Debenhams are doing so well they don’t my business. So out of pocket by almost £15.00 worth of telephone calls and a stress headache, frustrated and inconvenienced by incompetence I am still left three Christmas presents short....and still no explanation as to why they cancelled my orders. All of my other Christmas presents have been purchased the same way without any problem. So why is it that Debenhams fail to achieve what their competitors do well at!!! I have been shopping with Debenhams for over 15 years but in future I will be taking my business elsewhere until such time that their Customer Service returns to the standard I have come to expect.