This is from their website
We provide our subscribers with multiple opportunities to revoke their consent and opt out of our service. It is not our business or our policy to annoy anyone. You may easily cancel your SOS subscription and revoke your consent to receive calls at any time by (a) utilizing the automated opt-out procedure included in any message you receive; (b) calling 800-269-0281, or any WCA telephone number identified on the Caller ID; (c) sending an e-mail to
[email protected]; or (d) by completing the removal request form on this site.