Recoil spring on craftsman profession 30 Ft cord reel

It's very difficult to repair a cord wheel that's not working properly. There is a tightly wound spring that can cause harm if it comes uncoiled. It's best to try to find a replacement cord reel.

remove the recoil section and replace the broken spring

If no repair manual. It could be spring is broken. So I'd look for spring, and instructions to install spring. That should give you a good idea. I suppose the handle came off and lost the rope inside? Probably need new rope too. Same kind of instructions would apply in how to recoil if it's not broken.

Normally these small engines use a clock spring to retract the rope.
Remove the cover on the top and you should find the spring either broken or the tab where the spring end has broken off or jumped out of the mount.
You will need to pre-load the spring with enough tension to retract the rope.
Remove the pull handle from the rope, load the spring and then wrap the rope around the pully holding the pully and spring in the loaded position. place the end of the rope through the hole and tie up the handle. The rope should pull and retract without being installed on the engine.
Best explained here...
https://www.youtube.com/watch?v=tmo6oYOJJ4U

This is a common Kenmore problem. The cord may have kinked inside the cord reel, You can remove the top by taking the screws out some are hidden under the switch. If the cord gets too close to the edge of the reel it can bind. Do be careful as the spring in the cord reel can jump out and it hurts. I would take it to a dealer.

open up the unit, locate the cord reel, manually retract it to tighten the clock spring. should work again. lookout for broken plastics

It appears that the recoil spring has broken and you will have to pull it apart to replace it

I have had this situation before on a lawnmower. I didn't have a craftsman, but is probably the same issue. Basically, the spring that recoils the cord back in either broke or came unwound. When the mower is not running, the cogs on the pull chord keeps the cord from coming out. When the mower is running, the spring is not wound enough to hold the chord in and thus releases or doesn't hold it in.
Try pulling the pull chord assembly off and rewind the spring.

You have a broken recoil spring. Dis-assemble (pull-off) the recoil housing and check for proper dog alingnment, broken spring, or something jammed between recoil sprocket and engine block.

recoil spring is broken either replace spring or recoil assembly. your choice.