Sending STOP by SMS

[Thisisausername]

I get text messages that I want to unsubscribe from by sending ‘STOP’ - however whenever i try to unsubscribe it says ‘Message failure’ 

[Chalkychap]

Unfortunately @Thisisausername, SMARTY Mobile don't support short-codes for sending/replying to an SMS. This means you can't send STOP in response to a text message from a short-code.

There's a jointly owned UK company for mobile short-codes, which has more information about short-codes at https://www.short-codes.com/useful-information.