Locus Map Classic Heart Rate and Energie

Hi,
I'm using Locus Map Classic together with a Ticwatch 3 Pro (Wear)
It usually works fine.

But today i made a well-known walk about 20km and it showed "energie" of more than 3000 kcal (instead of 1500 i'm used to see). Would be nice to loose weight, but not correct.
The heartrate was about 128 (middle) and 206 (max) - which surely never was reached...

Question: 1. Is the heart rate a factor in the energie calculation? (not very useful because it depends on many individual factors like age, body height, ..)

2. Obviously the heart rate was doubled (why? - problem of the watch or BT..).

The system should show an alarm, if the heart rate without motion is higher than 128.
Btw in my age (64) a heart reate of 206 often results in death.

Kind regards
Thomas