How can I prevent double printing of packing slips for the same order?

[Annette12]

Hi, I am hoping you can help me how do I stop it from printing two packing slips (1 for digital products and 1 for Physical products) for the 1 location for the same order. 

[JingyE]

We had this same issue with shipping protection. We use ProtectMyOrder (a shipping protection app) and they did it all for us. Worked a treat.