15.2 These terms and conditions constitute the entire agreement between Samaritans and the User and supercede all other (prior or contemporaneous) communications and proposals, whether electronic or written, between the User and Samaritans.</p> <p>15.3 Any failure of Samaritans to exercise or enforce any of its rights under these terms and conditions shall not be deemed to be a waiver of any such rights or operate so as to bar the subsequent exercise or enforcement or any such rights.</p>16.