A young man sees his dead girlfriend through near death experiences.

From reading this logline, there doesn't seem to be a goal, conflict nor plot. I assume that isn't the case, so you might want to add those elements to the logline.

In the context of a logline this can be the inciting incident of the film. The premise has potential. His dramatic need to keep seeing his girlfriend can drive him to commit near death experiences. What stops him from doing so will provide the conflict necessary for a good story.

So two things. Justifying the dramatic need to keep seeing her (beyond the nature of their relationship), some unfinished business or maybe the dead girlfriend leading him towards her cause of death. This could also lead you to the second thing - what's stopping him? for instance, in this case, the forces responsible for her death could be preventing him from committing a series of NDEs.

Hope this helps.