Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. I found coupon for you. Check this out.
Link: Banggood product page
Coupon (79.18 USD): BG589b2e
(CouponsFromChina.com tip: you should apply the coupon 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): BG9d6746, BG08461c, BGb3ae81, BGWSCYT1, BG877e00, BGde2f67
(these coupons are old, so probably won’t work)
Price history and price alert
Do you need price history chart (for all/most countries) for Redmi AX1800 Wi-Fi 6 Router 128MB 880MHz? There we go.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).