To be brutally honest, you may have illustrated your own problem. I'm in my mid 50s and have always, always studied hard for my next job. I strongly suggest you either work diligently on someone else's project on GitHub or you create and publish something important to you, even if you might not get paid for it. The simple fact is, we old guys are like women or blacks--we have to be better than the average candidate to get the same consideration. Not a nice situation, but it's always been true. I have known this for 30 years and have been preparing ever since.