Fenix 6

Hello,

I just used my fenix 6 sapphire in an indoor swimming pool.

Can anyone please tell me why i had this result:

1st lap 11:26 600m

2nd lap 11:30 0m

3rd lap 11:36 500m

4th lap 11:47 0m

I mean why do i see zero metres in the 2nd and in the 4th lap? I did what i do every time, i pressed the lap button every 500-600 metres...ThinkingThinking

Thanks in advance!