Loop Plot Assigns Last Color to all Plot Curves

I'm plotting multiple curves based on different input parameters. I'm varying some of the parameters via while loop. Everything plots out just fine except for the line colors.

No matter what I do the plot function picks up the color of the last curve that is plotted and assigns it to the previous ones as well. I don't know why. The funny part is, the legend shows colors as they should be.

I've been browsing answers here and I tried every solution I found but the issue persists. Important to note is that the same happens if I don't specify any color at all, but I just cannot find where the issue is.

Please can someone take a look at my code and help? Perhaps I'm missing something obvious regarding how plot function works.

Again, apart from the colors, everything else is exactly as I want it.

Thanks.