Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China. Well, there is one coupon available right now.
Link: Banggood product page
Coupon (40.26 USD): elec
(CouponsFromChina.com tip: apply it 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): BGHU414, 502C6B, BGBFAFF2019, BGCITYADS2019, bGpAnDacHeCk, BGMPB2020
(probably won’t work, but you can try them out)
Price history and price alert
Price history (for all/most countries) for Mecool M8S Pro L S912 3/32GB TV Box is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).
Mecool M8S Pro L if this box developes a fault does it have a pin reset button on box and where is it thank you, if the box stays in standby need to reset it