Okay so let me explained. I had a working project with captcha there (https://github.com/mewebstudio/captcha) I did some modification and messed up and put it as one commit so I can't precisely see when stuff did get messed up but captcha is no longer displaying image. I though maybe it was the package issue so I tried 2 more packages and same things happens. I checked the GD library and it was working fine. Then I thought it was my server issue so I uploaded the code to the VPS same thing happened. After that I just created new project and tried to use the same captcha library and it work normally. I now have no idea how are all captchas messed up since code I added does nothing with them.