Weird "seam" on material after merging seperate meshes?

So I have this head model which had separate meshes for its eyes and the rest of the head, along with separate materials. So I joined the two meshes together and deleted the eye material, because the head model already had an eye texture.

After joining them I moved the UV’s for the eye area to where it’s supposed to go, but now there is this weird seam on the skin.

I’ve tried moving the eye UV around but the seam stays.