Adding and Subtracting Points on Knowledge Checks

I have a 6 knowledge check questions where participants can earn 5 points for the correct answer or have a point deducted for each incorrect answer. The questions are set for unlimited attempts and I want the points value to change on each correct and incorrect attempt. At the end of the six questions the participants will have a running total point score. I have a variable set "Running Points as a number type with a default value of 0. I have a trigger set on each radio button selected for each correct or incorrect answer.  For a correct answer the trigger says "Add Running Points to Value 5 when the user selects the correct radio button." For an incorrect answer "Subtract value 1 when the user selects an incorrect radio button. The number will change but it will not add and subtract correctly on each slide. If the participants selects an incorrect answer, the running points should subtract 1, then if the participant tries again and gets the correct answer the running points should show 4. It is not actually subtracting the 1 from the 5 when the correct answer was selected. Any help would be appreciated.