Aliexpress
Click here… to search for Xiaomi DXRACER Ergonomics Office Lounge Chair on Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China. There is one great coupon!
Link: Banggood product page
Coupon (580.78 USD): 7d18f7
(CouponsFromChina.com tip: coupon code has to be applied in shop’s 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): TTxBG10, 2019SPEDM, BG3CSUM, AFfbG10, 502C6B, BGBFAFF2019, BGCITYADS2019, BGMPB2020, BGAFF7OFF, bGhOnEy10, BGSS10%SW, bgshOOp10, BGHWDEALS888, Email5
(there’s a little possibility that old coupon will work)
Price history and price alert
Price history (for all/most countries) for Xiaomi DXRACER Ergonomics Office Lounge Chair is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).