3wk old using breast as pacifier :(

Has anyone else had this problem. My dd feeds well during feeds (20+mins) & sleeps in 3-4hr chunks at night.  But getting her to nap for more than a few minutes during the day is near impossible & she goes through hours of sucking (none or minimal) swallowing) & dozing off on my breast & the second I take her off she's awake and crying. Has anyone been able to successfully overcome this & how? She won't settle by any other means; no rocking, swinging, walking will do & a bath only settles her till she comes out.