Measure a fully charged Ni-Cad or Ni-MH cell when it is fresh from the charger. It is not 1.2V, instead it is 1.4V to 1.5V. Its voltage gradually drops to about 1.0V as it discharges.
Lately, most days are cloudy with no sunshine. When the sun does shine then it is low in the sky so the solar panels do not produce much power.
Sunrise today was 7:07AM and it will set at 4:58 but the daylight is brightest at about noon. My garden lights glow dimly in the evening for maybe one hour now.
The batteries, battery contacts, switch, LDR and leads on the LEDs rust away because my solar garden lights are cheap ones made in China. The solar panels get sunburned.
I replace the batteries, LEDs and clean the battery contacts with CLR. Most of my solar panels are finished.