Based on Article 7, letter g of Law No. 8 of 1999 on Consumer Protection, it is stated that the delivery service provider is obligated to provide compensation, reimbursement, and/or replacement if the goods and/or services traded do not conform to the agreement, due to negligence on the part of the delivery service provider. Law No. 8 of 1999 on Consumer Protection clearly regulates the rights and obligations of consumers and business actors. However, the delivery service provider J&T Express has not yet optimized the provision of compensation and reimbursement to business actors using J&T's services. The purpose of this thesis is to explain the form of legal protection that business actors can obtain when they suffer losses due to a transaction cancellation by consumers, caused by negligence on the part of the delivery service provider, and the resolution efforts that business actors can take regarding default by the delivery service provider. The results of this research indicate that J&T Express's responsibility for delayed product delivery is the return of the product. Compensation in the form of a refund for shipping costs will only be provided after negotiations between the business actor and J&T Express, where the business actor requests their rights due to the harm caused by using J&T Express's services. The resolution efforts that a business actor can take against the default of J&T Express include negotiating or seeking alternative dispute resolution outside of court. If J&T Express refuses the proposed resolution, the dispute can be settled through legal proceedings in court.