How could I change bad karma when I created it? Should I accept it? What is the best way to understand it?

Well, there is really only one way but it is so complex not many are able to do it. First you need to wait until a full moon, next strip naked, climb on your rooftop to the peak. Stand on your head and bark at the moon while shoving a carrot up your butt.

Since "karma" is imaginary, just "imagine" that everything is okay and going your way.

Make compensations.

Jesus.