It most likely has a broken dial string. To fix, you will first need to obtain a diagram as to how the old string was connected. There should be a sticker on the chassis that contains the radio chassis number. With this information, you can look up a Sam's Photofact service manual for your unit (Howard W. Sams has published service data for many consumer items since '46). Now, armed with the dial stringing diagram, you will need to order some new dial string. I think places like
www.tubesandmore.com still stock dial string. Now, you get to have all sorts of fun trying to restring the dial cord. It's possible that you can do the job without a diagram; but, it will be a trial and error process and there may be a lot of cussing involved.