activity heart rate cure fine, but average and max values are WAY OFF and the activity appears as a gap in my daily heart rate? Recorded with HRM tri some sync problem?

Hello I did a strength session today and the heart rate curve looks fine to me, but the post-crunching seems odd to me. It has only considered the first 7 seconds of a 62 minute session with the heart rate as picture submitted. 

Average heart rate calculation is way low, and max is also 40 bpm off lower than it's supposed to be. This made the aerobic and anaerobic training effects also near nill and useless. I need these to figure out my resting period no?

heart rate during strength training7 seconds of strength out of 62 minutes?

Heart rate was recorded with HRM tri away from watch but uploaded post training. The download was fine and the heart rate curve looks accurate, but everything else is off. 

Also the heart rate for today has a gap during the traning session. A though the upload from the HRM tri was not quite fine but I did it twice according to https://support.garmin.com/en-CA/?faq=BatdMMuLrk703sVqdI5069all day with gap