Aliexpress
Here are coupons that you can use.
Latest coupon and price update (UTC):
Banggood
Banggood warehouse is located in China. Only one coupon available!
Link: Banggood product page
Coupon (12.59 USD): AFfbG10
(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): 46FWC3, S20BW, 8FWC3, BGFWC3, 12blitzw, 2019SPEDM
(these codes were not working in latest coupon update, but you can check them out anyway)
Price history and price alert
Check out price history chart (for all/most countries) for BlitzWolf BW-FWC3 5W Wireless Charger.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).