He already said > Lost private key, he may forget his password too.
In that case, how you gonna help him?
If I've lost my password or can't access my wallet, but still have private keys, then it could be recovered.
Everyone could recover their bitcoin through private keys obviously, without need your service.

I'm not sure about how you recover bitcoin wallet, but if someone using electrum wallet which has private keys, but never export it. Then forget his password, can you help this kind of lost?