unexpected behavior of atan2

[nicogallice]

Hi I'd like to draw some Bode-like plots,
the atan2() function seems to not work correctly at some combination of values.
I managed to re-create the minimal working code to show the problem:

I am using atan2() function with a non trivial dependence on x and some parameters defined as declare function=

• \addplot[red, domain=1e1:1e10, samples=1000] {-atan2(x/wo,(1 - x*x/wo/wo))}; gives an expected behavior up to some point (red curve);
• \addplot[domain=1e1:1e7, samples=1000] {-atan2(x/wo/Q,(1 - x*x/wo/wo))}; does not seem reliable (black);

\documentclass{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\pgfplotsset{compat=1.18}
\begin{document}
	\begin{tikzpicture}[
		declare function={
			d=0.9;
			Rl=100e3;
			L=200e-6;
			C=400e-9;
			wo= (1-d)/sqrt(L*C);
			Q=wo*Rl*C;
		}
	]
		\begin{axis}[xmode=log]
            \addplot[domain=1e1:1e7, samples=1000] {-atan2(x/wo/Q,(1 - x*x/wo/wo))};
            \addplot[red, domain=1e1:1e10, samples=1000] {-atan2(x/wo,(1 - x*x/wo/wo))};
		\end{axis}
	\end{tikzpicture}

\end{document}

The following plot is informative of the problem:

I am compiling with pdflatex (plot produced on overleaf but reproducible on my PC).