You can create price alert here, copy coupons and view price history. You probably want to know what is the best price?
2A, Output 42V 1.7A, Non-rechargeable environment Please avoid charging in the environment lower than -20 ℃ and higher than 40 ℃, Suitable Only suitable Mijia scooter, Turn current 100-200mA, Input 100-240V 50-60Hz
Aliexpress
There’re some similar (or not) items on Aliexpress
Click here to search by yourself. Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. There is no active coupon in my database right now (for Banggood).
Link: Banggood product page
Price: $-3
It looks like this item is out of stock in Banggood. If you found it then please send me the link. I will replace it.
Click here to search on Banggood!
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k and https://couponsfromchina.com/short/5cd
Old coupons (from the oldest to the newest): 0e7f33, FBCOUPON1, bgshOOp10, BG11SHOP, 13f142, BGCuponation10, BG10OFFAFF, BGwhielabel, BGbd0cbe, BG10OFFAFF1, BG1b4b1d, 8Couponsde, MVC8SPRING, 8BGwbg2204, 2203ActiesNL, tRaDetRaCKeR, 8wEbgaInS5, BG71c041, Cuponation9, BGb24021, BG8ReviTrage, BGcoupon8off, BGGutscheine, BG00c906, BG8OFFCOUPON, TTBLACK5
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for Xiaomi M365/Pro Electric Scooter Charger 42V 1.7A 71W is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood and Aliexpress (only if product name will be the same as on Banggood and I will post it on social media though, so it’s more like Banggood price alert)).