Entity will not react to bullet damage


I am currently working on a SWEP that creates mine entities that are set to explode whenever a player or NPC come within a certain range or when the mine is damaged at all.

However the mine does not seem to react to hitscan bullet damage at all, but it does react to explosions when utilizing the function ENT:OnTakeDamage()

I have tried looking this up and have found a couple of posts with the same issue but none with the solution.

Is there something I am doing wrong?

Code, for test purposes.