Maybe you didn't give it enough time to acclimate. 1 day from wherever it was before is not really a lot of time for plants. They are slow adjusters. Hardening off, takes at least a week.
I would find a way to give it some shade. I put a chair in front of or on top of some of my plants to give them shade. I let them wilt, then give them shade. They perk back up after about 30 min to an hour, then I expose them to the sun again. Fast way to harden them off, but takes a lot observation time.
Good luck and happy gardening!
