Extreme CF cards freeze Windows File Explorer

I have 2 Extreme CF memory cards for my camera, 32 GB & 64GB. One is a year old and the other 2 weeks. They use to work on my PC just fine… Now they freeze it up and aren’t being read by the File Explorer. I’ve done nothing different. I even tried reformatting one in the camera. My other CF card, a regular (non-Extreme) card, 5-7 years old, works fine. Why would the Extremes just stop working on my PC?