Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Cannot get it past an error indication

I have been trying to use this item ever since I purchased to keep track of my blood pressure and almost every I try to use it it keeps giving an error indication.I put it on as tight as I can in accordance to the directions given and start it. It pumps for a few seconds and then stops with a flashing 'E'. Only a very few times has it gone through the process to measure my BP and it frustrates me. As I indicated I put it on as tight as I am able and it fails more often than not to give me blood pressure. I most likely wasted my money on this tirm!!!