I can't even imagine someone claiming to restore a lost Bitcoin how and from where?
This is just something that is not possible to do because I know too well that any bitcoin stolen or mistakenly sent to wrong address can never be restored all less you have a direct contact with the person who owns the address. But however only newbies can fall for this cheap scam methods.
Same thought that comes to my mind when I see people seeking for help desperately after losing their coins, especially on social media from total strangers they know nothing about. This will only make you vulnerable and expose you to more danger and severe pain because at this point, you are emotionally down and can do anything to get help. Note this, if you lose your coin(s), it is gone and cannot be reversed except in few cases where you are close to the supposed beneficiary.
Sometimes there many in the room so as one person call or drop and others also drop different information nd recommendation and those who don't know anything will call the contact thinking that the person they contact is a good person. And if you call one person in that place they will give the phone to one another making the thing more real.
They are in some sort of chain network, working hard to convince their latest prey that whatever help or business they are offering is genuine, if you are not smart enough to avoid them, they'll feast on your funds.
In this current age where everyone is vigilant, where news about scammers and their mode of operations have spread round like wild fire, no one is supposed to fall victim to these scammers. Avoid strangers by all means, especially those ones that offer unsolicited help and juicy offers.