I have 1 phone & am not about to rely on someone else to provide their phone if I need to find mine - how do I send sms commands to locate/lock the phone using a PC via email, App or my carrier's web portal

Hello, I have an LG G4 and I love its knock code. Does anyone know if I can make it work with Sophos' remote lock, because it doesn't seem to accept it? Knock code does have a PIN code as an alternative unlocking method... Thanks