Pathway Lights Not Charging

I bought a set of solar path lights. They are charging very slowly if they are at all. This may be because they are underneath a large tree in front of my house. Yesterday, I moved the light closest to the front door to the backyard which gets direct sunlight for 4-5 hours, but it took several hours for the light’s battery to go from 25% to 31%. It was 23% this morning and I brought it inside to charge, but less than 30 minutes later it went from 23% to 0%.