Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (20.69 USD): band10
Coupon (20.69 USD): BGCuponation10
(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): 99Q1, TTxBG10, 2019SPEDM, BG3CSUM, AFfbG10, BGBK15
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Here is price history (for all/most countries) for Bakeey Q01 Smart Watch Black.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).