Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. I am tired of searching coupons, but I found one for you…
Link: Banggood product page
Coupon (14.10 USD): BGTY704CP
(CouponsFromChina.com tip: apply code in your basket (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): 99a5c1, AFfbG10, BGCITYADS2019, BGTS204, BGMPB2020, BGAFF10OFF, bGhOnEy10, BGdragonBoat, BGCAMP01, bgshOOp10, BgoFErTaSchInA10, BgcLuBofErtA10, BGZPBC15, BGCuponation10
(system checks these coupons on every price check (like once per 24 hours), but you can check them out anyway)
Price history and price alert
Price history (for all/most countries) for Xiaomi Pinlo 500ml Water Bottle is here.
Price records source(s): Gearbest, Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).