Best answer by Bradley_Boost
I've made a few minor changes to your question, so that its more accessible for users to find in case this can help them too.
Boost is an energy supplier and has no connection to MoneySuperMarket whatsoever. MoneySuperMarket are a third party broker that offers comparisons in different products and services for customers.
It sounds like you may have switched to us through this third party rather then directly, of which you should've been advised of all the charges. This is something Boost would've advised you of upon switching.
You may wish to take any issues or concerns up with them if you feel mislead in anyway!