Hi @piyush7829 , Why dont you do that using JoltTransformation as well. I think you can do it before split or after depending what is the json is and what is the expected new output. JsonJoltTransformation  processor is very powerful and it allows you to use Expression Language which mean you can reference attributes in the jolt spec and assign them to new key. For example if you want to assign the value of the attribute ${series_id} to new key called series_id , then in jolt spec you can do that as follows: [ { "operation": "shift", "spec": { ..... "#${series_id}":"series_id" ...... } } ] If you need help with the jolt spec please post sample input and expected output and I will he happy to help you. If you find this is helpful please accept solution. Thanks   ... View more

@piyush7829, Change the setting of the EvaluateJsonPath "Destination" Property to flowfile-attribute instead of flowfile-content. Setting this property with the later value will change the whole flowfile content and wont create the attribute you are looking for in the replacetext processor. if that still doesnt work, make sure to check after the EvaluateJsonPath to see if the "match_id" attribute was created and populated with the correct value, if not then I need to see the response from the GetMongo processor to make sure the correct path is being set in the EvaluateJsonPath.     ... View more