If my hand is on the display of my Dell Latitude 5285 while writing, the pen input is no longer recognized as soon as the active pen is lifted from the display. it is necessary to take your hand off the display and only put it down again while the pen is touching the display.
Unfortunately you have to repeat this procedure after almost every drawn line. Alternatively, you could let your writing-hand constantly float, which is absolutely impractical for several reasons.
This does not appear in any other programm.