When you flip the rewind lever upward (back on or off, lens extended or collapsed, shutter tensioned or not), the sprocket wheel should turn freely.
If the small lever next to the viewfinder does not allow the sprocket wheel to turn freely, then it is possible that the post is installed incorrectly.
Usually, this means that you have to remove the retaiing screw and the lever and rotate the post 180 degrees and replace the level. Test it before replacing the retaining screw.
I cannot say with certainty that this is the problem with your camera. I just offer this as a possibility.
If the camera has never been serviced, then it might be something else.