Thanks to techyv I was able to resolve my problem. Before, the mask tool on my Photoshop is not working. But with the help of this site, I was able to fix it by resetting the Photoshop preferences. And just a while ago, I asked for help again about my typing tool that is also not working and the people here replied and help me fix it. Now, it’s all working fine. Thank you very much techyv!!!