my XZ have develop black dots when taking photos. just bought one month. sigh.

hi. i bought an AP set XZ 2 months ago. today i cant turn on my phone after washing it using tab water (all flaps close properly). brought it to the shop. they say got water damage and cant do anything about it. they say if i bought ori set also cant claim warranty. they just advise to let the phone dry for a week. sigh, so much for a water resistent phone. now really regret buying this phone. anybody have any advice on what should i do?

kinda like a ripoff isnt it? promoting something that can go 1.5m underwater for 30mins but fail even when wash using tap water for few mins. sigh.