Does your baby rejects Frozen breastmilk? If yes, how did you solve the problem?

It could be due to the difference in taste. Sometimes the taste of the milk would change due to the storing process. For example, there may be excess lipase in the milk due to the storing and causes the frozen milk to taste soapy after being thawed. The way to go about this is to scald the express milk first before freezing (you can refer to this blog post on how to scald the milk: http://simplyrebekah.com/2010/05/03/excess-lipase-scalding-breast-milk/).