Hello! An agreement is a contract and has legal effect. Generally speaking, unless otherwise agreed by the parties, creditors are free to assign their creditor's rights. However, if the creditor's rights and debts are to be transferred at the same time, the consent of the other party is required. The annual card transfer can be a pure transfer of creditor's rights or a simultaneous transfer of creditor's rights and debts, depending on how the agreement is agreed. In the first case, the gym has no right to prevent you from transferring the annual card. In the second case, you have to get the consent of the gym.