I was recently at the sea and we went through a slightly deeper passage with water and stones to come back. I slipped on a stone (moss) and fell into the water, unfortunately with mobile phone (Huawei p8 lite (2015)).
Jz is my question if I still have warranty to have it repaired / replaced, have the phone only since 1em year
A warranty damage is not there. That pays you ev. An insurance, if it was insured accordingly.
Or should it be waterproof?
That is certainly not a warranty case. The occurs only when the phone is broken without external impact. You are guilty yourself.
The warranty, or statutory warranty, only covers damage caused by the manufacturer. For example due to manufacturing defects. Self-inflicted damage, the manufacturer does not have to wear.