False advertsing of product

I went to baby city and was told that the Motorola monitor was a good system to monitor baby and I should not get an angel care set as this would be cover everything. Upon purchase the first fault was it did not monitor babies heart beat. I took it back to baby city, and was told they cannot take it back as I did not have the non-English books that it came with. (I did have everything else in it original packaging). The second disappointment is the battery life only lasts a max an hour. How can a product like this be sold of the selves at the cost that it comes with, when it is such a poor quality item.