Manikanda,
You cannot access another transaction's values from the backend. You need to make sure the transaction values you require are sent up with each transaction. This is done with transaction merging on the client to correct previous obsolete variable values. Your problem is that you execute transaction 2 and transaction 2 has an update step on it that eventually runs a backend steplet. You execute transaction 3 that changes the status and does not get reflected in transaction 2 when it gets sent up. To fix this, create another edit transaction against the same workorder object. Set only the status property from object. Set the merge settings on the transaction to "Merge with any Transaction". Uncheck the "Discard Null" check box. After you apply transaction 3, and this new transaction step followed by another Apply. This will update any previous pending transactions that are waiting to be transmitted with the current status. Use the Agentry Test Environment (ATE) to inspect your transactions so you can debug this process and make sure it is working properly.
Jason Latko - Senior Product Developer at SAP