Outback Bob is correct, in that form makes the fire. A positioning of the body that provides for as little tension allows longer, smoother strokes.
A fire board is wood, so not often 100% uniform density. A slight bend in cottonwood in one board I have yielded harder wood. I could get a coal easier out of that spot compared to the softer, and straighter wood, a few inches away/ Same fireboard, but a few inches mattered.
I worked as a guide, instructor, where the students started all fires by friction, and some flint and steel. If a fire set is not productive, make another, as wood varies not only between species, but in location and even in a few inches distance on a branch.
Keep at it. Check in and let us know how it is going.