The challenge is in OSINT category. So let's start googling his name.
The first result is a youtube channel. Searching in info section we can retrive the flag


# FLAG
X-MAS{subscribelikesharethanks-bobi:)}

Original writeup (https://github.com/Internaut401/CTF_Writeup/blob/master/2019/X-MAS%20CTF%202019/Bobi's%20wHack.md).