Aliexpress
Here are coupons that you can use.
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Xiaomi Mijia MJSTS1 Pro Robot Vacuum Cleaner [EU] (-3 USD)
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 (599.99 USD): BGCNXMPU
(CouponsFromChina.com tip: put item in your cart and apply coupon code there 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): BGCNXMPRM, 7bcdf9, BG10OFFAFF, BGCNXMSPR, BGCNNEWXM, BGwhielabel, BGCNXMP, BGCNXMUPA, BGCZXMSTP, BG10OFFAFF1, BGHU0775, BGCZXMPRE, BGCNXMSR, BGCZTAXMP, BGCZXMPR5, BGCZXMPT, BGDUXMCPR, BGCZBFXMP, BGBFCZMP, BGCZPLMP, BGCZPLXMPE, BGCZPLXMPV, BG49c64a, BGIT202203, BGGR2202, BGIT2222, BGHU1708, BGc03d95, BG64a506, BG4a9f05, Terence, BGDC0304, BG1dfbbc, BGcabddf, MVC8SPRING, BGf6521b, BGb8a9e8, BGmiproB, BGmiproA, BG622yb29, BGPLXMPU, BGjune30d, BGmiproDYF08, BGjuly12e, BGxiaomipro
(these codes were not working in latest coupon update, but you can check them out anyway)
Other warehouses/versions
This item is available in 1 another warehouse/version!
1. Europe – Xiaomi Mijia MJSTS1 Pro Robot Vacuum Cleaner [EU] (-3 USD)
Price history and price alert
Here is price history (for all/most countries) for Xiaomi Mijia MJSTS1 Pro Robot Vacuum Cleaner.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).