Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. Only one coupon available!
Link: Banggood product page
Coupon (29.32 USD): BG51f436
(CouponsFromChina.com tip: this code has to be applied in your 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): BGHY6P, BGBK15, BGBAK15, BGAFF10OFF, band10, BGBFY612, BGWRIBAND10, BG5c2353, BG2c7fea
(these coupons are old, so probably won’t work)
Price history and price alert
Price history (for all/most countries) for Bakeey Y6 Pro Fitness Tracker is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).