How can I make VL02N non-editable completely?

Hi Experts,

I have come accross a client requirement where I need to make VL02N non-editable when the shipment status is greater than 5, then all the delieveries assigned to shipment shoud be non-editable.

Can anyone please tell me any BADI, EXIT  etc where i can add the custom code  to achieve the same?

I have been trying but could not find anything of relevance.

Thank you in advance.

Best Regards,

Piyush Kaushik.