Eight days ago (on 2023.04.16) I wrote about a quick test. I am using it on Tenerife since 2023.04.21.
Three days ago it was run out of energy. One blue light blinked. I let the solar panel charge it, and then I tried to charge my smartphone (Motorola Moto G22) with it. I also let the power level of the battery of my smartphone to 0%. So the power bank charged it from 0% to 35%, after the solar panel charged the battery of the power bank for two days.
So this power bank is not good to charge the smartphone to 100% every day, but it is good for charging the smartphone a little bit in power outages, and in emergency situations.
Better than nothing, but to properly charge a smartphone battery, a better solar panel is needed.
Of course this (the 35% battery charge every two days) is on Tenerife, where the sun is mostly shining. This percentage is probably much less in other places, where the sun is not shining that much.
Have a nice day. All the best. Greetings and much love from Tenerife, Canary Islands, Spain.