Intervals wrong pace?

Today I had a suggested workout of:

Interval 1: Warmup 10 mints at 7:00 per km

Interval 2: Run 15 minutes at 5:45 per Km

Interval 3: Cool down, 10 minutes at 7:00 per km

I did it and it was showing the right time per km but the intervals show a different pace per km.

In the 1st screenshot you can see how during the race interval 2 I was running from 5:30 to 5:40 per km,

In the 2nd screenshot you can see that the interval pace displays a different value, 6:17 per km average.

How is that possible? is it maybe doing the average of the previous interval as well?

On a related note, If i look at the time adjusted to the incline, it shows the right average speed of around 5:35 for that interval but... I was running in a totally flat 400mts track...