Revolve a line about $z$-axis

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I have to find the parametrization of the surface which comes from the revolution of the line

$$(0,4+3t,1-3t)$$

about the $z$-axis.

I tried to do

$$\sigma(t,x)=(0\cdot\cos(x),(4+3t)\sin(x),1-3t)$$

with $x\in[0,2\pi]$ but when I try to plot, I don't get a cone. What's wrong?