Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. You can get coupon down below.
Link: Banggood product page
Coupon (62.36 USD): BG10OFFAFF1
(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): BGAFF10OFF, BGNH52, BGCuponation10, 13f142, BG10OFFAFF, BGwhielabel
(there’s a little possibility that old coupon will work)
Price history and price alert
Price history (for all/most countries) for Xiaomi LEGA Graphene Hot Compress Neckband is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).