Aliexpress
Here are coupons that you can use.
Latest coupon code price check (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (9.89 USD): BGAFF10OFF
Coupon (9.89 USD): bgshOOp10
(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): aff7off, 13ca80, S20BW, 502C6B, bgs10bw, 12blitzw, BGss10%bw, AFfbG10, BGVDay10%off, bGhOnEy10, BGXMI15, BGdragonBoat, BGSS10%SW
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Check out price history chart (for all/most countries) for BlitzWolf BW-S10 30W Type-C PD+QC3.0 Wall Charger.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).