Strange Normal map, Roughness map lighting effect on material textures

Hi there! Currently new on making my own textures for my upcoming game, I was wondering what’s the problem why some surfaces and such seem to have weird lighting effects when exposed to any light.

Here’s a demonstration:

Notice how grass seems to be bright when not exposed to light, but is dark when exposed to it.
This is however more apparent when exposed to direct PointLights, such as:

I would like to know what went wrong here, as the process of me making my normal maps was generating it on Photoshop, and also for my Roughness I just made it monochrome with high brightness and contrast, here’s a demonstration of the texture I did:

Sand Color

Sand Normal Map

Sand Roughness

Any feedback is appreciated! Thanks!