Be a little bit more firm with your touch maybe? Happens to me a lot when I go get a massage. I always ask for a woman and they always seem to be a little too gentle. I'm always telling them "harder please!" lol I also find that instead of using your palms and fingers some particular back aches require something round so one day I requested the masseur to make a fist and and work my lower back a little. It felt amazing! Two fisted shiatsu!