Parked document approval

[Ulagapiragasam Vanathy (RBAU/ISY) *]

Hi,
I am using Standard workflow WS10000051 with the sub workflow WS10000055
(account assignment)
parked document approval. I am at the initial stage of the design.
 
The workflow triggers once the parked document is created, but it is in
error status and
I get the following message. Any idea why
 
Expression '&ACTIVITY_000043_TASK&' for task: Error during evaluation or
incorrect data type
Element SUBNR not in source container
 
Workflow 'Document Parking (Frame), Parallel' no. 000000006001 step
0000000038: See message for b
Element ACTIVITY_000043_TASK not in source container
 
 
Regards
Vanathy