why i get this black line in themiddle of the character face?

i don’t know from where is the problem my texture are clean and when i zoom in the black line go away i use toon material i painted the texture in blender
when i zoom in can’t see the black line in her face

when i zoom out i see it

Prepare a .blend and upload that. Include the face and pack its texture in.

Typically this is caused by not having large enough margins for your UV islands on your texture map. If you post your texture map that would be helpful.