Core Viewpoint - A consumer has raised concerns regarding the quality of the Redmi K50 smartphone after experiencing a screen defect, leading to a dispute over repair costs with Xiaomi [1][4][10] Group 1: Consumer Complaint - The consumer, Mr. Cheng, purchased a Redmi K50 for 2469 yuan during the 2022 Double Eleven shopping festival and reported a sudden appearance of a green line on the screen after less than three years of use [1][4] - Upon seeking repair services, Mr. Cheng was informed that he would need to pay 710 yuan for the repair due to the phone being out of warranty [6][8] Group 2: Quality Concerns - Mr. Cheng discovered multiple reports online from other Redmi K50 users experiencing similar screen issues, leading him to question whether the device has inherent quality problems or defects [3][10] - The consumer argued that quality issues should warrant free repairs even if the warranty has expired, citing instances where other users received free repairs despite being out of warranty [6][8] Group 3: Xiaomi's Response - Xiaomi's repair center stated that they could not provide media comments but would relay the concerns to the relevant departments [3][10] - When contacted by a consumer posing as Mr. Cheng, Xiaomi's customer service indicated that repair costs depend on the engineer's assessment and that free repairs for out-of-warranty devices are subject to specific conditions [10]