Multiple Linear Regressions, Legend does not work

Question

I am working on a diagram with tikz. There are two linear regressions in the diagram, but \addlegendentry does yield weird results for the second plot. Instead of the red star (which i would have expected) the legend shows the black line from the regression.

\begin{tikzpicture}
\begin{axis}[
    grid, grid style=dashed,
    scale only axis,
    axis y line = left,
    axis x line = bottom,
    ylabel = {Drehzahl $n$ in \unit{\per\minute}},
    xlabel = {Ankerspannung $U_{A}$ in \unit{\volt}},
    ymax = 2500,
    ymin = 0,
    xmin = 0, 
    xmax = 250,
    xtick distance= 25,
    ytick distance= 250,    
    legend pos=south east
    ]
\addplot[only marks,
    mark=star,
    blue,
    ] table[row sep=\\]{
    X Y\\
    240 1502\\
    225 1402\\
    207 1301\\
    192 1200\\
    175 1101\\ 
    160 1000\\
    145 902\\ 
    127 799\\
    112 707\\
    };
\addlegendentry{Nebenschlussmaschine}
\addplot [color = black,shorten >= -0.3cm,,shorten <= -0.3cm] table[row sep=\\,
    y={create col/linear regression={y=Y}}, mark=none]
    {
    X Y\\
    240 1502\\
    225 1402\\
    207 1301\\
    192 1200\\
    175 1101\\ 
    160 1000\\
    145 902\\ 
    127 799\\
    112 707\\
   };
\addplot[only marks,
    mark=star,
    red,
    ] table[row sep=\\]{
    X Y\\
    60 1338\\
    110 2247\\
    };
\addlegendentry{Reihenschlussmaschine}
\addplot [color = black,shorten >= -0.3cm,,shorten <= -0.3cm] table[row sep=\\,
   y={create col/linear regression={y=Y}}, mark=none]
   {
    X Y\\
    60 1338\\
    110 2247\\
    };
\end{axis}
\end{tikzpicture}

Is there some problem steming from using two regressions within one axis ? Thanks!