Charge 5 - swim function stops during swimming

[MMex]

I have a Charge 5 and I normally swim 80 laps. Lately the Charge 5 stops while swimming in the middle of a lap. I am especially worried as - apart from not counting the laps right - it then also releases the water lock and that might affect my fitbit. Any help?

[Surfista]

It won't hurt your watch if the water lok turns off. 

The water lok just shuts down the heart monitor because Fit Bit says it is not accurate when wet.

My Charge 5 is not always accurate in the lap count. I can tell because I always swim an even number of laps but sometimes it registers an odd number.

Not the best swimmer's fitness watch.

[MMex]

Good to know that I don´t have to worry about this, but still it makes no sense that the Charge 5 suddenly decides that I have swam enough. It stops the exercice sometimes at 10 min, 30 min,.. in the middle of a lap without particular reason.