You agree to accept responsibility for any and all activities or actions that occur under your account and/or password, whether your password is with our Service or a third-party service. You must notify us immediately upon becoming aware of any breach of security or unauthorized use of your account.<br> 5.3 You may not use as a username the name of another person or entity or that is not lawfully available for use, a name or trademark that is subject to any rights of another person or entity other than you, without appropriate authorization.