Can't extrude closed shape

[ericengvall]

https://imgur.com/a/CB5fUEA

I painstakingly designed this to duplicate an existing plastic clip for my car.  When I try and extrude it or just select the plane, it won't select.  What could be wrong and how can I correct it?

I did remove all of the constraints as I went.  Is that somehow the issue?  I thought fusion didn't need the constraints to work.  

Any help is appreciated.  Thank you in advance.  

Edit: actually, I may know why it is not closed.  At times, I would drag and drop points of the outline onto other points to get the shape I wanted.  So how do I tell fusion those points are coincident.  Maybe add coincident constraints?

[ericengvall · Accepted solution]

LOVE IT.  I figured it out.  The places on the outline where it showed dots for corners was where the two lines were not coincident.  All I had to do was click coincident constraint and then drag a box around the points...boom, it joined them.  I love fusion!