DMN Error - "Exception while evaluating decision with key 'null'"

Hi Everyone,

I am getting the “Exception while evaluating decision with key ‘null’” error when testing DMN table using rest API in postman. The URL is : http://localhost:8080/engine-rest/decision-definition/key/Discounts1/evaluate

I have only one row with two columns in the DMN table. Not sure about the reason for getting this error. Kindly advise.

Below is the request details.

"variables": {

    "adviserChannel": {

        "value": "Test"


    "hasLumpSum": {

        "value": true




Below is the error message.

"type": "RestException",

"message": "Cannot evaluate decision Discounts1:5:4862a153-1d08-11ec-9949-f859715ce90f: Exception while evaluating decision with key 'null'"


Below is the XML from the DMN table.

<?xml version="1.0" encoding="UTF-8"?> adviserChannel 8% LIC discount on lump sum cover strips "Test" true "8% LIC discount"

Hi @skbabu,

Can you please share your dmn model…

Discounts2.dmn (1.9 KB)

Hi @hassang ,

Thanks for your reply. Please find the attached dmn model

Hi @skbabu ,

The definition key used in the REST call is different than the one specified in the model
Please try below call

Hi @hassang ,

Thanks for the update. I have updated the correct definition key and All good now.

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