Can somebody help me to find the solution?

I think there is something wrong with the definition of bvw1. If I use dsolve (in soln) with only bvw as Initial Condition,

I get a solution but if I also insert bvw1 as an Initial condition soln won't appear.

Here's what's written in the image:

'Imagine the course of a planet around a star with L=0.5 and e=0.7'

Solve Keppler's differential equation with Initial Conditions:'