That looks like a dual recording on Feb 13. Same time, same date. One on your Garmin and the other on Wahoo System. You can delete one of them or the hidden feature applies (duplicate detected).
Do you have other duplicates like that on file?
What is your Decay Method set to under Profile Settings?
While you can ride for extended periods without BTs it’s always a good idea to put in some maximal efforts now and then. Over a year without a BT is too long of a gap. 
Here’s how to resolve the situation.
Outdoors: A couple max sprints (10-20secs), rest, then perform an escalating set of intervals >TP with short recoveries riding to a complete failure point on the final interval.
Indoors: Ride one of the “fitness test” workouts in Slope mode, exceeding targets if able, and always to failure on the interval designed for that purpose.
See this post for details – From old trainer to smart trainer. Set FTP - Training - Xert Community Forum
Also note you can flag any activity if you wish to exclude a signature calculation you don’t agree with, but retain the strain score analysis.