possible cause
1. The rated current of the mobile phone charger is too small, while the current of the mobile phone is large, and the mismatch between the two causes the charger to work in the overload state for a long time, which is easy to damage.
2. The mains voltage is too low or too high, causing the charger oscillation circuit to work improperly.
3. The mains waveform is distorted, or there is serious high-frequency interference, causing the charger oscillation circuit to work improperly and burn.