Computer Network Info Services review: fraudulent charge on my mastercard

I found an unauthorized charge made to Computer Network Info Services on 3/23/2019 for the amount of $7.57. I was unfamiliar with the company's name, so I Googled it. I found dozens of people complaining about fraudulent charges (some even repeating monthly charges) in varying amounts some as high as $499! Citi MasterCard agreed to credit my account the amount. How do these scammers keep getting away with this? I tried to find a legitimate website, phone number, of address for Computer Network Info Services, and I am unable to find any information.