plotting – Seamless ContourPlot for a conditional function

When I try to create a ContourPlot of a continuous conditional function, Mathematica leaves a “seam” in between the two regions demarcated by the conditional. How do I fill this seam?

fn(x_, y_) := If(x < 2, y/x^2, y/(2 x))
ContourPlot(fn(x, y), {x, 1.5, 2.5}, {y, 0, 2})

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