What are you using to record the activities?

If it's an external device (watch, bike computer, etc) Strava will use the activity type the device sends. Check which activity profile you're using on the device, maybe try using a different one to see if it changes from E-Bike to something else to prove that is the issue.

Nope.  Have been using same bike computer for years. It’s Strava by their own admission. My Garmin does not have e-bike option. 

I would be very annoyed if Strava changes my ride uploads to ebike and refuses to fix this wrong behaviour. But I’m sure  ​@ActivityFix third party app will help you to create a rule to revert future rides to the ride type automatically