GL-XE300 Doesn't charge devices

I bought a GL-XE300, came completely empty. Worked for 3 days, then stopped charging. If the router is turned off, then it takes 20 hours to fully charge! if it is on Does not charge at all constantly discharged. What could be the problem ?? how it can be eliminated. There is no possibility to hand over the guarantee, since I am in another country! Help me please.!!!

Seems something wrong on the battery.
If connect the charger, can the XE300 work normally?

Да все нормально работает , если на зарядке 24 часа, и он выключен то зарядит.
Если нет, пишет что зарядка идёт и роутер разряжает