Aliexpress
Click here… to search for Xiaomi QICYCLE Bike Tricycle on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (233.32 USD): 7bcdf9
(CouponsFromChina.com tip: coupon code has to be applied in shop’s cart after clicking “Proceed to checkout”. Click to copy code and open shop)
Exclusive Allowance Coupons: https://bit.ly/3xWgD9k
Old coupons (from the oldest to the newest): 1e3426, bgsport, TTxBG10, BGOD1, BGss35, AFfbG10, 502C6B, BGBFAFF2019, BGCITYADS2019, BGMPB2020, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGSS10%SW, bgshOOp10, BgoFErTaSchInA10, BgcLuBofErtA10, BGCuponation10, BGHONEY2110, BG10OFFAFF, BGwhielabel
(I don’t think these’re gonna work, but you can try ’em out anyway)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi QICYCLE Bike Tricycle.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).