The issue is that when using
guide_legend you have to put pass
color a vector of colors in the order they appear in the legend, i.e. the “High” color should come first, “Low” second, … As you provided no data, I could not check but
guides(linetype = guide_legend(override.aes = list(color = line_colors[c(3, 1, 2)]))
should give you the right colors for your linetype legend.
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