Aliexpress
Click here… to search for Bakeey H9 Smart Watch Black on 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 (47.69 USD): band10
Coupon (47.69 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): c34a65, 502C6B, BG15D, TTxBG10, BG3CSUM, AFfbG10, BGBK15, BGBAK15, BGAFF10OFF, bgshOOp10, 7d18f7
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Price history (for all/most countries) for Bakeey H9 Smart Watch Black is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).