Unfortunately, any removal of activity is permanent. You cannot recover deleted activities from your Dashboard. 

However, you can: 

• import this activity, using a .gpx, .tcx, or .fit file, from your sports app to our app (but you'll have to follow a few steps, and use our web version if there is one 😉): here is how to do it.
• write to our team in order to recover your activity: contact us.