my friends lost his coins from offline wallet when he was chatting online on facebook messenger
sure he can't restore his coin
so how can protect offline wallet ?
Maybe he was victim of phishing sites when he talks mostly on social media and links was sent to her and after clicking then you are already a victim ,you know how to protect your wallets from offline and online?stop engaging in social media and never click any links camping from random people instead from a tested people only so you are not prone from these scammers And hackers
I think there are still a lot of possibilities to consider on why your friend lost his funds in his wallet. But the closes thing that I can't think of is a malware that is inside of his computer. Other things such as saving it in another computer or he saved something important in messenger that someone might've seen.
That is the only reason why because mentioned that she was talking to a messenger and maybe giving a link or something like clickbait