How to change PO numbers of Customers

Summary: PO Number on the AR is grayed out

Followed below steps to update PO Number on Transaction:

1. Navigate to Billing -> Manage Transactions.

2. Search for transaction. (How to edit the transaction?)

3. Click Show more link to expand and click Miscellaneous tab to view PO Number

4.PO Number is grayed out. How to edit PO Number?

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