Hi Nipun, Thank you for your feedback on our eve pillows. It's a shame to hear that you don't find them comfortable and that you find the cover quite slippery. We will share this feedback with our product development team. We understand that these pillows were complimentary with your mattress purchase, so if you would like to gift them to a friend or keep them as spares, you are welcome to do so. Kind regards, The eve Sleep Team.