Error on Pushing Express Checkout Test REST API

#1

Hi

I am integrating Paynow using the REST API method via HTTP POST.

I managed to successfully initialize the API call for the Initiate a Transaction.

I am now on the second part of the API Reference which involves the Express Checkout Transactions where I am trying to do a test payment from our server using the success number 0771111111.

According to the docs, I need to use the fields from the Initiate a Transaction and then specify the payment method field for the Express Checkout API Call.

I then copied all the field values from my Initiate a Transaction call and added them to the Express Checkout API call and added the phone field to indicate that it is an EcoCash/One Money test transaction.

I then receive an error message “Invalid Hash” despite the same Hash working for the Initiate a Transaction call.

Screenshot link of success response from Paynow on Initialize a Transaction API call initialization

Screenshot of error message from Express Checkout API Call initialization

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Screenshot_70.jpg803x799 83.4 KB

Your assistance is greatly appreciated.

#2

The Hash you generate must include all the fields you are sending. By using the previous Hash it will not including the extra values in the Hash generation and hence and “Invalid error”

#3

The only new field I have added to the Express Checkout API call is the phone field which only contains the test number 0771111111

Where do I add this in the string in order to generate the Hash as this info is not available in your documentation.

Thank you for your reply