Core Viewpoint - The article discusses the consumer rights issues arising from the "green line" problem in smartphone screens, affecting major brands like OPPO, Vivo, Samsung, Xiaomi, and Huawei, highlighting the inconsistent after-sales service and warranty policies among these manufacturers [1][9]. Group 1: After-Sales Service Policies - OPPO and Vivo offer a warranty period of around four years, while Xiaomi, Huawei, and Honor typically provide one year of warranty service [3]. - OPPO announced free screen replacement for devices with green line issues within four years of purchase, while users with devices older than four years can receive discounted repair services [3]. - There are significant discrepancies in after-sales service experiences among OPPO users, with some receiving free replacements while others are denied service due to lack of purchase receipts [4][5]. Group 2: Consumer Complaints and Experiences - Many consumers report unreasonable demands for proof of purchase, such as requiring original receipts and packaging, which complicates the warranty claim process [4][8]. - Some users have successfully obtained free screen replacements after escalating complaints through various channels, despite being initially denied service [4][5]. - The article notes that even within the same brand, different service centers may apply different policies regarding the green line issue, leading to confusion and frustration among consumers [7][8]. Group 3: Technical Background of the Issue - The green line issue is a common fault in OLED displays, potentially caused by various factors such as chip failure or circuit issues [9][11]. - The problem has been linked to specific batches of screens supplied by Samsung, affecting multiple smartphone models [11]. - High temperatures and humidity are noted as conditions that can exacerbate the green line problem, with summer months being particularly problematic [12]. Group 4: Industry Response and Consumer Trust - There is a growing consumer expectation for a transparent and fair after-sales service system, especially in light of the marketing claims of high-quality products [13]. - The article emphasizes that the lack of a unified standard in after-sales service undermines consumer trust, as users feel that the service does not match the promised product quality [13].

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]