Good karma and bad karma grow and flourish inside a person. He himself knows and can understand this.
The fertilizer and water he is putting, he is putting it in good karma or bad karma. To prove this balance, our Mahatmas have said again and again, “If you plant acacia tree, how will you get mangoes.”
So clearly our ancestors have said again and again. The fruit we get is the result of the karma done by us. No one can change that fruit by his will.