A complaint about an item you purchased

Dear Sir or Madam, I am a loyal customer to your brand. I have recently purchased a laptop from one of your stores. However, the experience is not as pleasant as it should have been. Even I, myself, would be glad if I didn't ought to write this complaint letter. Unfortunately, having an exceptional laptop computer is crucial for the correct development of my work. Last week, I went to your store in order to get a brand-new computer. Despite asking desperately to multiple staff for information and advice, my questions were never answered. Therefore, I decided to get the most expensive laptop. If only I had known what would happen next. On using it for the first time, it worked for a while but, out of the blue, it would stop. I thought maybe the battery was flat. Thus, I decided to charge it once more time. Afterwards, the laptop did not turn on. I have tried to contact the customer service several times on the contrary they were never available. I felt that this is an example of extremely poor service, and I would like to request a full refund. Furthermore, I would like an apology from the manager. Yours faithfully, Sthephanie