Did you go through all steps in this post?
If you are using the full Strava history import (Strava sends mail with link to archive of your original data), be patient after pasting the link and starting the process. This can take a while depending on the size of the archive. You may not see anything happening at first because in the background, there’s a list of ‘todo’s’ that is being made. The import itself only starts when the list is ready. For the same reason, a recent ride may not appear directly, being queued after the import process.
As a check for a working connection, just connect Strava, make a short dummy activity and let it sync. If that works, then start the full history import and let it run for whatever time necessary.