Non-perceived piano lessons of a semester card cannot be refunded or credited or recouped. It does not matter whether you are due to illness, due to private, professional or school commitments or because of holidays etc. Have to cancel. But there is a so-called "swap list," where school students have the opportunity to exchange with someone at short notice. This happens to each other-if you know that you cannot visit the hour at regular time, you may find someone to swap.