You can't attend the training yourself because you broke the contract first and the training institution didn't do anything that couldn't deliver the service. It's very kind of you to refund half the fee. The full responsibility for this incident lies with you. Before signing up, you should know the possibility that you may not be able to attend the course during the training period, or agree with the training institution what to do if you cannot attend the training, instead of blaming the other party for not being able to refund the fee to you for your own reasons!