Poor Customer Service

I purchased an item from them and when I opened it the user manual said that if you had certain medical conditions you had to consult with your GP first. When I questioned the store they were very unsympathetic after been aware of my medical condition and when I questioned them about the user manual they weren't even aware of it. So there product knowledge is very poor and now after I alerted them about the manual they are hiding behind it and don't want to allow me to return the unused item. Absolutely shocking.