Rainbow Key can't sign a contract with Alipay, which means that when you try to sign a contract with Alipay, the signing process can't be completed smoothly. This situation is generally caused by abnormal Alipay account or network connection problems. You can log in to Alipay again or reconnect after disconnecting.

Rainbow Key Alipay is a mobile payment application, which integrates the payment function of Alipay and can complete the payment operation through the rainbow key application. In addition, Rainbow Key Alipay also provides rebates, discounts and other preferential activities to provide users with a more affordable payment experience.