Visit this site where you get instructions on how to get Cambridge Analytica to tell you if your personal data has been harvested and what it is they know about you.
The data protection agent for Cambridge Analytica is its mother company SCL Elections, which is a UK company where European Data Protection rules still apply.
One rule is that every data subject — that’s you if they have your name and number — can ask anyone who holds data on them to tell them what they know about them.
It will cost you 10 British pounds and some copying and pasting.
But, wouldn’t you like to know?