My Daughter Had The Mirena Iud Removed About Three Months

my daughter had the mirena iud removed about three months ago and has continuous bleeding since then. she went to the md, he did a pap and blood work that all came back normal. He prescribed provera and told her to take it for three months and have a return appt in six months and that does not sound right to me. What could cause bleeding that long after having the iud removed and why take a hormone for three months and tell the patient to come back in six months?