Code compiles fine, can't find include files when packaging

I have Visual Studio Community 2019 set to Shipping, I’m also packaging in Shipping in UE4. When I build the project in VS19 it compiles successfully, and also when I compile in UE4 it compiles fine. In the VC++ section in project properties in VS, I have all the needed include folders set up already.
After all of this, packaging fails when I try to package to Windows 64bit. It only reports one “Unknown Error” but I’ve noticed it not finding the include files. Here’s the relevant log section:

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Any help would be very much appreciated. Thank you very much!

Finally SOLVED!

I had to include the full path to the file in each #include line.

Example: #include "Mayhaemsters/Actors/C_PickupItem.h"