About service Singapore

ita posible apple charge some ammount for confidential issue?, cause I get bad service from apple singapore. They charge to pay somthing that confidential issue about my phone. In the first time they tell me some issue about my phone damage and they said my display is from third party, but I always change my display from apple cause I have applecare+, and they invetigate again and they come with annother issue that my phone have liquid damage dan no signal and liquid damage not covered by applecare+. WTF.. I know applecare+ covered liquid damage, and they come again with another issue my back glass broke, since I drop my phone to apple store they inspection my phone all side and no damage with back glass, now they come to issue I’ve to pay some amount for confidential issue WTF dude.. 😔😡