How do you remove Mirror and SubSurface seams? I'm fairly new to Blender and am trying to make a human face mesh using the Mirror and Subdivision Surface modifiers. When I attempt to do so, the result shows this seam in the mesh and does not have the mirror align properly, as well as the subsurface creating a rip in the center mouth. How do I resolve this issue?

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Thank you for the comments, I've got it to work now! Issue was I needed to tick Clipping then apply Subsurf after the Mirror modifier.