1. The power is out
Bluetooth headphones are battery powered. If the battery is out of power or damaged, it will often disconnect automatically.
2, the interference source is too strong
Bluetooth headset is working at 2.4g frequency, this frequency also has wifi router, cordless phone and 2.4g mouse. These are relatively strong sources of interference.
3. The headphones are of poor quality
In particular, refurbished headphones, just bought normal, with a period of time out of the problem.
4. Bluetooth headset compatibility problem
Some Bluetooth headsets, used on other brands of mobile phones, sometimes automatically disconnect. It's a compatibility issue.
The light went out after a while, maybe the battery was broken, or the indicator was broken. Another is that the charging interface is not firm, or the interface is loose.