Cadence sensor isn’t accurate - recommendations

Hi all - I’ve been riding Zwift for a couple years with my Kinetic Road Machine and recently decided I wanted to start a training program. The problem is, although Zwift says it is paired with my cadence sensor, my cadence never goes above 70 or 72 no matter how fast I’m pedaling. I use Zwift thru AppleTV. I would buy a separate cadence sensor but I read on this forum that the Kinetic sensor doesn’t work. Looking for recs on how to solve this problem.

When I can get my cadence paired, it is spot on, however, I find the speed to be either considerably too fast, or too slow.