How I update Xiaomi Mi 8 Lite?

[Miyakutsune]

Phone I have XiaoMi Mi8 Lite, it not update. Update app say not able connect to network, I try download Manuel, but it say it not able verify package. I try clear data and reset, but it not work. I try change to India raigon change but it not work. I not have access to PC so please note tell me I need PC. I buy phone in amazon.com new. Android version 8.1 phone info global stable, miui version 10.2.2.0 ODTIMIXM I try everything person tell me online but not one work but I not want give up so if you able help I very thankful.