# Polar and Parametric Plots not showing up

I bet this has asked before, but I can't seem to find an answer anywhere.

I have x and y functions which, individually plotted, are showing up fine, but when I try to plot the parametrically, the graph does not show up. I absolutely cannot figure out why this is occurring, and I've tried simpler functions (such as x=sin[t]), which work, leading me to believe it has something to do with the way I solved the differential equation.

    k1 = 9*^9*(1.6*^-19)^2;
me = 511*^3;
mp = 938*^6;
ℏ = 6.59*^-1;
U[r_] := -k1/r;
V[r_] := U[r] + l[r]^2/2/μ/r^2;
L := n*ℏ;
ϕ'[r_] := L/me/r^2;
F[r_] := -k1/r^2;
μ = (me + mp)/(me*mp);
u[ϕ_] := 1/r[ϕ];
l[r_] := μ r^2 ϕ'[r];
n = .1;

sol = NDSolve[{D[D[u[ϕ], ϕ], ϕ] ==
u[ϕ] - μ/l[r[ϕ]]^2/u[ϕ]^2*F[r[ϕ]],
r == 30, r' == 5}, r[ϕ], {ϕ, 0, 4 Pi}];

X[ϕ1_] := r[ϕ]*Cos[ϕ] /. sol /. ϕ -> ϕ1;
Y[ϕ1_] := r[ϕ]*Sin[ϕ] /. sol /. ϕ -> ϕ1;

Plot[X[th], {th, 0, 2 Pi}]
Plot[Y[th], {th, 0, 2 Pi}]
ParametricPlot[{X[t], Y[t]}, {t, 0, 2 Pi}]

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Note the First@sol part:
X[ϕ1_] := r[ϕ]*Cos[ϕ] /. First@sol /. ϕ -> ϕ1; 