So it's coming from the files on the other side. I guess if they wrap around too much they start effecting the side it wraps onto. I'll just crop my images more to stop them from wrapping around so much.
Here's a screen shot of me blowing the image up really big and taking the the one facing you down. Not sure if there's a fix for that or if I just need to crop more.

ok, do you use the 3D model from Dimension or it's oyur own 3D model?
You can try this to perfectly set and place the image 😉
1 Select the object
2 Go to the menu : Object/exports uvs
3 set to 2048 or 4096px the export
4 open the PSD
5 Show the layer texture grid
6 Save the file
7 Replace the base color of the material with the psd
8 Now you can see all the grid on the 3D model and you can check if your design is ok
9 Return to your psd hide the texture grid layer and save. Maybe you need to replace the psd file by the last one
10 You should see your design


Let us know if this solution help 😉
You can use it for all your design.