Aliexpress
Here are coupons that you can use.
Latest price update (UTC time):
Banggood
Banggood warehouse is located in China.
Link: Banggood product page
Coupon (25.11 USD): Cuponation9
Coupon (25.38 USD): BG8ReviTrage
Coupon (25.93 USD): BG00c906
(CouponsFromChina.com tip: paste coupon code in your cart and click Apply 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): 50DGPO, vipupgrade8, BGHomeandGarden, e2bcea, FCR119, FCR1088, frc799, 99FCR, 0404digoo, c4ed05, 502C6B, 30glamp, TTxBG10, BGDigoo15%, AFfbG10, BGFCR1, BGORGN19, 0e7f33, BGDG15, FBCOUPON1, 20%DG422, BGDGASG, BGHome15%, BGHOMEA15%, BGHBHJ105, BGAFF10OFF, BGCuponation10, 13f142, BGHONEY2110, BG10OFFAFF, BGwhielabel, BGJUN244, BGLIG12, BGISXP0901, BG10OFFAFF1, BGd0b05d, 00c906, ADMITAD2212, 2022ACTIESNL, Terence, BGLED2203, MVC8SPRING, 8BGwbg2204, 2203ActiesNL, tRaDetRaCKeR, 8wEbgaInS5, pROMo8cuPoN, BGf94f14, BGLED2206
(sometimes old coupons work, so you can check them out (this site checks them on every price update))
Price history and price alert
Price history (for all/most countries) for Digoo DG-FCR-1 Solar LED Lamp is here.
Price records source(s): Banggood
Click on image to enlarge. 
You can set price alert (for Banggood).