Redwood : Disable receipt correction if receipt is invoiced

Hi Redwood Community,

I’m working on a Redwood UI page and trying to implement a rule to restrict receipt correction completely if an invoice has been created for the transaction.

Here’s the issue I’m facing:

• The system currently restricts correction only if the corrected quantity is less than the invoiced quantity, but allows correction if it’s above that — which doesn’t meet our requirement.
• I want to block correction entirely if any invoice exists against the receipt.

Challenge:

In the page's input parameters, I can see a list of transaction IDs, but:

• I'm unable to assign this input parameter to a variable