Karma “業” is a common word nowadays as you can see a service “Credit Karma”. Karma is like a homework that you didn’t accomplish in the past lives so you brought it to this life. For example everyone marries with a wedding vows “I promise to be faithful to you until death do us part”, no one expects to divorce at that time, but soon or later around 50% of vows fail even there is an old tradition in Japan, “Your little finger and your spouse’s finger was connected with a red thread since you were born.” Actually karma is the tendencies of the mind that have been created while reincarnation. Tendencies, once they have formed, influencing your thoughts or actions bring not only troubles but also good fruits in their lives. Usually to resolve a bad karma, we bring it into this life aiming to accomplish it by correcting your tendencies. For example once you divorced you plan to marry with same person again in this life to try to improve your tendencies through accomplishing your marriage, unfortunately it fails again sometimes. However, life is not the only resolving karma, that is another part of the life. Mainly we try to evolve our souls through reincarnation.
If you see yourself as you are cursed or have a bad karma, try to form the good tendency of the soul by analysing your karma like what is the origin of this incident, what tendency caused this karma, once you find it, then improve it so that you can solve your bad karma.
In Theravada Buddhism, it is said that Buddha never reborn, because He has awakened and is not necessary to reborn to solve his karma anymore. However in Mahayana Buddhism He comes down on earth at his will to save all the people who have been suffering from their life problems by preaching new teachings adjusted in the age.