Ramp is imho way to steep. Once she knows how to use a longer one she might use this too, but I would make it at least twice as long. or with a step at the lower end if there isn't enough room. As it she pretty much has to jump down.
When I got my buck he had some troubles too the first time in his life he could leave his hutch, I had to send some kits to show him the ropes
I agree, that ramp is too steep. Also remember they are essentially wearing fuzzy socks, so it's probably hard for a rabbit to want to go up a ramp with little traction. It may be helpful to cut carpet pieces to fit in the large gaps, in addition to making it less steep.