Of course you can cancel any contract that has not been completed.
But there are costs and steps and process associated with the cancellation, that you agreed to when you signed the California Assoc. of Realtors contract.
Did you agree to Mediation, arbitration, do you have a lawyer, do you know RE lawyers charge
more than Divorce lawyers, do you know that the chance to collect is Zero, as there
is an option to file for Bankruptcy for the seller.