I call these scammers and try to get them to think about what they do, and once or twice it has worked and I’ve gotten an actual discourse going about why they scam people. But most people deny that they are a scammer, and say they are a legit company. So I’ve found a way to prove that they are not, and it is as simple as copying and pasting the number into google. Any real tech support company will have a website linking their phone number. If you find no website about the company, prank away. But there is the off chance that the person who posted the number is posting a real number, so I encourage you to do this. But perhaps the scammers have a website that could be unsecured and dangerous, so do this with caution.