Please, could you revise my formal letter?

To whom it may concern,

I am writing today to complain about an incident that took place last week at your vending machine in the train station. This incident has left me with little money and has caused me some drawbacks.

On the morning of Friday 27^th February I decided to get a book to read on the train from your vending machine. I selected the book that I wanted to read, but the machine immediately told me that there was a system error, so it did not give me the book or any change.

Some hours later I contacted the company responsible for this vending machine, which informed me that they could see no reason why the machine had stopped working, because they had already controlled it some days before. Then, they told me that they did not know how to solve this problem, since after my incident the machine restarted working normally. Moreover, they informed me that they were not sure to give me my money back, but, if they did, it would take many days.

I am very disappointed with the treatment I have received from your company. I had to catch the train the same day, so I now have no money until I’ll come back home. I expect you to send me the money as soon as possible. I would also like to do not have to pay something for this inconvenience. If I do not hear from you in the next 10 days, I shall be forced to report this incident to the police.

I look forward to hearing from you very soon.

Yours faithfully.