Looks like you’ve applied some crease to some edges.
To check if this is the case, go into edit-mode.
Select all vertices.
See if there is below the median x,y,z boxes also a “Median Crease W” box. If there is and the value is non-zero you’ve found the problem. To solve it change the value to zero and you’re done.
If it doesn’t work you could also post the .blend-file so we can have a look at it.
EDIT: I just recreated your file and had a different vertex count than you (130 instead of 150). So you probably have some double vertices.
- Select all vertices (in editmode)
- W-key --> option 6 (remove doubles)