Generally, the deposit cannot be refunded, but if the supplier breaches the contract, the deposit can be refunded, that is, double the deposit. If the supplier refuses to refund the deposit, it may bring a lawsuit to the court. The two parties only agree on the circumstances under which the deposit should be confiscated or returned in double. If there is a special agreement, the agreement should be followed.
 [Legal Basis]
 In Article 586 of the Civil Code, the parties may agree that one party shall pay a deposit to the other party as security for the creditor's rights. The deposit contract is established when the deposit is actually paid.
 The amount of the deposit shall be agreed upon by the parties; However, it shall not exceed 20% of the amount of the subject matter of the main contract, and the excess shall not have the effect of a deposit. If the amount of deposit actually paid is more or less than the agreed amount, it shall be deemed that the agreed amount of deposit has been changed.