a) If the device LED is not blinking then there are chances that it might be already connected to other Mobile phone/Laptop

b) Power ON the device and immediately check if there is any voice prompt or not

c) If Mobile phone is not showing any Bluetooth name then restart Mobile phone's Bluetooth

d) Turn on and then turn off the Airplane mode in Mobile phone

e) Restart the Mobile phone

f) Put the device on charging for 30 min to ensure if the device is charging or not

g) In case of no LED or no voice prompt and no charging indication, there are chances that the device might be dead.