Hacker is requesting for money

Problem/Goal: My friends PC got hacked

Context: Friend is looking for a job, saw an email and clicked a link, unfortunately, all important documents got 'encrypted' by this hacker and requesting money from him to 'decrypt' it. He already gave them 30k as of this moment and still asking for more.

Previous Attempts: None, my fried does not want to negotiate and compromised the documents as he badly needs it for his other job.