Rainflow Fatigue Damage

I am new to using the fatigue life damage package and am currently experiencing large inconsistencies between what the software is telling me for accumulated damage my test produced compared with the manual calculations I've done using DEWESoft's Rainflow algorithm. I did the manual calculations to both validate and better understand what the software is doing. My end goal is to test our product for a sample amount of miles, calculate the damage caused up to that point, then extrapolate how many miles we can expect to failure.

As it stands, the area we tested should experience an infinite amount of life from knowing how the product has performed in the field. My manual calculation (see attached) shows that the damage accumulated was 1.91*10^-14 compared with DEWESoft's damage of 0.0021. Being off by this many decimal places between the two is concerning. I know the product will go much farther than the 1500 miles I calculated with DEWESoft's accumulated damage approximation.

At this point I'm stuck and not sure how to proceed. I could use some guidance in figuring out what I must be doing wrong in the software to be arriving at such a large amount of damage.