Take a close look at the bottom of that 2 -- I think you'll find your answer there.
Okay, CLOSE to the bottom. It appears you have a closed mask path, but I'm not sure. And the upper part of the 2 doesn't actually join to the lower, horizontal part. I think if you re-work the mask path so you get a good outline of a 2, and not an upper part hanging above the lower part, you'll be a lot more successful.
Reshape cannot deal with your kind of shape. You will have to morph all the segments separately on separate layers.
First, you've got to carefully analyze how you want the reshape to work, match vertexes and do some planning. You've converting a whole bunch of vertices to nine. The first vertex in the 2 is near the top left, the first vertex in the rectangle is at the top right. Things are going to get wonky. You have to plan your morph by matching the vertices to the movement you want.
The first thing I would do is simplify the 2 a bunch. You could eliminate about 80% of the vertices by just using the bezier tools correctly. It also looks like you have notches in your 2. If these notches are critical to the design then create them with a track matte and make the 2 one simple closed path and just fade out the notches as the 2 starts to morph. The next step in the process would be to put the first vertex in the 2 at the top left corner and set the first vertex in the rounded rectangle in the top left corner. Then you decide what parts of the 2 you want to move to the other corners of the rounded rectangle and pick pairs of vertices in the 2 to match with the corners. You just have to keep track of these vertices in your head or make notes on a piece of paper. The last step is to count the number of vertices between the matching corners and add them to the rectangle. Something like this:
If you start at the first vertex of the 2 and the first vertex of the rounded rectangle
Then move clockwise around the paths you can see all of the corresponding points. Your image will move along these points as it morphs.
My first attempt shows some problems and some folding that are going to happen with the lines that cross. A little repositioning or reworking of the paths may minimize this problem. You are never going to get the shapes you have drawn to work correctly. You'll have to modify the paths.
To get the notches to move just have to keyframe the track matte layer so the notches go away at the appropriate time.