applying hold on Line level via OM Extension Script - error

Summary:

I have write code in OM Extension for apply line level hold but going to error code as below:

import oracle.apps.scm.doo.common.extensions.ValidationException
import oracle.apps.scm.doo.common.extensions.Message
import oracle.apps.scm.doo.common.extensions.HoldResult
import oracle.apps.scm.doo.common.extensions.CreateLineParams

// Run the extension only on sales orders that are on hold.
def lines = header.getAttribute("Lines")

while (lines.hasNext()) {
def line = lines.next()

// Correct field name for transaction line type (assuming it's from the `line` object)

if (line.getAttribute("TransactionLineTypeCode") == "SL_BILL_ONLY") {


    // Apply hold to the line