I wonder if it was hard to begin with. If it bent the first time without breaking it may not have been hard enough.

Pix would help. How much angle is on the bend? If it's folded completely over, I'm back to my first concern, it wasn't hard. If it's a shallow angle, then the blade may be in the spring hard range, but not the very hard brittle range and you could possibly maybe, very judiciously, tap it back to straight.

Michael is correct though. "Working" the material too much will increase the local hardness and it could fail at that point anyway.

The other option is to send it to a smith/grinder who knows their heat treatment and have them straighten it. First anneal, straighten and heat treat correctly etc.