PayUMoney is a popular payment gateway that provides payment solutions for merchants and individuals. it is the flagship product of Naspers. The operations of PayUMoney are available in approximately 17 countries across the globe. When your customer requests a refund, you need to request it using the PayU module. 

Short Direction: {Amazcart> Dashboard> Payment Gateways> Payumoney> Test/Live> Payumoney Key>  Payumoney Salt> Payumoney Auth> Gateway Logo> Update.}

You need to activate your account with PayUmoney to get the key and salt details on PayU Dashboard. Your account gets activated only if you have submitted all the basic documents while onboarding. 

1- Payumoney

2- Test/Live

3- Payumoney Key

4-  Payumoney Salt

5- Payumoney Auth

6- Gateway Logo

7- Update it.