プラスエリアは掴むが
4Gのバンド19は誤植だったはず

https://www.mi.com/global/max3/specs/

Supported frequency bands

GSM : B2, B3, B5, B8
WCDMA : B1, B2, B5, B8
TDD-LTE : B34, B38, B39, B40, B41(120M 2535M~2655M)
FDD-LTE : B1, B3, B4, B5, B7, B8, B20