What do you mean by breast milk suddenly stopped. You may have reduced the feeding hence due to lack of Stimulation the supply has reduced. With low supply the baby would loose interest as well. Use a breast pump to stimulate four to six times a day for atleast twenty minutes. Once the supply increases try latching baby again. In the mean while ensure that you do not use a bottle.

start power pumping. every 2 hours.. it will stimulate.. have subudana n methi seeds soaked in water overnight.. put methi seeds, sauf, ajwain all in one overnight n next day have it