Fenix 6X (V12.20) Lap pace alert first lap always 0:00

Can someone have a look at the following thread?

https://forums.garmin.com/outdoor-recreation/outdoor-recreation/f/fenix-6-series/248107/fenix-6x-v12-20-lap-pace-alert-first-lap-always-0-00/1346405#1346405

Using Fenix 6X (V12.20), and test three different Data Faild.  

First lap always get a 0:00 lap-pace on the alert-screen

From lap 2 everything is ok, in GC the data for the first lap is also ok

I am wondering how a datafiled can broke the "lap alert" screen. Can anyone help?