Some major problems with your deck;
1- The deck was stained too soon. Pressure treated wood must be allowed dry before staining. Can take a few weeks or longer.
2- Two coats of stain. The first would have soaked in a little and the second is on top, forming a film. Films peel on a deck!
3- "Sprayed 2 coats of Behr redwood solid stain in between rainy days." The wood was wet. The stain can't dry when the wood is wet.
Get the contractor to completely remove all stain from the floor. Allow to dry for a few weeks then restain.