In JSON request, value of array item is not getting updated while forwarding the request to the live endpoint

Requirement - If the value of a[i] = "ABC" then update the value to "XYZ" and forward the call to the live endpoint 

Issue - We have a[i] = "ABC", so we need to update the value to "XYZ" But this value is reflected only in warning logs and not in the request body.

Expected - The value in request body should be updated as "XYZ" and call should be forwarded to live endpoint.