We have a requirement to capture the Customer name in the Payable Invoice of Drop Ship Orders

We have a requirement to capture the Customer name in the Payable Invoice distribution lines of Drop Ship Purchase Order,

I have created a DFF in the distributions line of the AP Invoice called CUSTOMER NAME from which I have planned to capture Customer Name and I have tried to create Form Personalization like below one for capturing the customer name but this Form personalization works only when I go through the Lines Tab of Invoice Workbench, Click the distributions of a line which leads to distributions form and then save it from there for every distribution lines but the requirement is we have to populate the customer name in the DFF of the Invoice distribution lines once we validate