Getting stuck often boils down to one of two things. Either you don't WANT to write, or you don't know WHAT to write.

In the case of not wanting to write, or feeling personally blocked, you need to take a look at yourself as the writer. What thoughts and internal struggles are preventing you from moving forward?

In the case of not knowing what to write, you need to look more closely at your story. What about your content is causing a disconnect that is preventing you from moving forward?