The line has to be called every morning, inside a narrow window, with your ID keyed in from memory. Clockwork makes the call and texts you what it said.
It calls twice, and both calls have to hear the same thing before it will tell you anything. If the recording is unclear, it says so and tells you to call the line yourself rather than guessing at an answer.
Your check-in ID is entered once, stored encrypted, and keyed in for you on every call. It is never shown back to anyone, including in your daily text.
Every text quotes the recording word for word, right under the answer, so you can check it against the line yourself.
Every testing company has a different set of prompts. We call yours ourselves and work out the exact sequence before you are switched on. Tell us who tests you and we will tell you straight whether it can be done.