For WDJAVA, maintain this settings.
If your using standard task Maintain the parameters as below for the task TS18900034 in ecc side t-code SWFVISU
APPLICATION ClaimAdvanceApproval_IN
DYNPARAM appno=00002
PACKAGE sap.com/ess~in~claims
SYSTEM_ALIAS SAP_LocalSystem
In case, If your using custom task also, then maintain same above parameters for your custom task.
Once you maintain above values in ECC then re-register the UWL once in portal side.
This also mentioned in this thread Problem with IT declaration approval task in UWL