I took a look at your character.
It appears you've parented the metarig to your character which creates an infinitate loop. blender stops that from happening to avoid crashes. The solution is very simple:
Unparent your character mesh and try again. Here are some pictures to help you.
Loop in Parents is the error you get. Looking at your outliner, you can see the metarig is a child of the character mesh. Click and drag it un clear the rig of its parent.
Again, selecting the character mesh first and then the rig second in object mode. Press Ctrl+P and parent with automatic weights.
Now the rig works perfectly. Easy mistake to make, easy solution to fix it.
I would also note that the hierarchy is a bit strange. I would parent the thigh bones to the pelvis .L and .R NOT the spine bone but it depends what you want.
Here is your edited file in case you need to compare.
I hope that helps.