Definitely consider a protein treatment followed by a deep treatment, or try Curl Junkie Repair Me, which is a protein treatment and deep treatment in one.

When I have damaged by hair with heat (and also with dyeing it), I use the Repair Me followed by a deep treatment (even though the Repair Me is supposed to combine protein with deep treatment).

I've sometimes dyed my hair and been so horrified with the results that I dyed it again (permanent dyes) the very same day. My hair becomes limp straw - without a curl in sight. That's when I follow the routine above.

Good luck - your curls will come back for sure. There just sick - not dead. As long as your hair isn't breaking or splitting, they will revive. Please let us know how it is going.
2/c and some 3A. Modified CG.
Protein sensitive
Highly porous. Color over grey.
Best 1st day method: Super Soaker
Conditioners: Curl Junkie Beauticurls Strengthening Conditioner,
Deep condish: Curl Junkie Curl Rehab
Stylers: Experimenting with cones & sulfates while the dews are high.
Sometimes try roller sets - classic glamor but I prefer my curls.
Every day is a gift