When I replaced my awning fabric several months ago, I watched a bunch of YouTube videos to see how it was done.
There is a recoil spring on both ends. When I removed the fabric tube, there were two different approaches, Pin the back recoil spring, or unwind it then rewind it after installing the new fabric.
Regardless of what you do with the non-ratchet end, follow the procedure and unwind the spring on the ratchet end, counting the number of turns.
When I had mine apart, on the ratchet end, I specifically looked at the ratchet assembly as mine was difficult to release. I bet you'll find the pin that holds the ratchet paw is either broken or the shaft with the ratchet paw is broken where the pin goes through it.
Good luck, take a couple photos.
Here is s link to my fabric replacement
Replace awning fabric | 2001 Coachmen Mirada 300QB