Mine had the same issue last time. I'm not sure what is the reason, though heard that it could be growth spurt. What i did was, give her small amounts of milk. If she refused, then i stop feeding. After that, I'll hold her to sleep, and when she is more deeply aslp, I'll put her down gently. Usually it works. It is very tiring, but i felt that babies at this young age need to be held to feel secure, thus i did that. This is a phase that will pass, so hang on!