I just had this issue with my power reel this morning on our 2017 3721RL. Sounds from this thread that my issue is with the 'studs' coming out of the reel. A big thank you as always to all those that helped troubleshoot this in the past.
Just to add a little value myself I came across the YouTube video below showing the process to access the power reel. Hope this helps anyone with this issue in the future.
I haven't decided yet if I will try this repair myself or pay a professional.