Can't discard activity

Hi,

I have a Venu updated to the latest firmware. 
I ended a strength activity and then tried to discard it, but I just couldn't find how to do it. I swiped the trash can after the activity ended, but coulnd't get past the next screen no matter where I swiped. The upper button did nothing and the lower button just returned me to the activity.

  

Any ideas?

Thanks