Thank you for reaching out to the Samsung community! We would like to inform you that lock and mask app password cannot be reset if you forgot the password. The application data like (Images, videos, music and important files) can be moved to SD card from My file or you can take backup via smart switch in your PC. To use lock and mask app again remove the accounts and factory reset the device.
Be sure to hit ♡ when you find an answer that works for you. For Further assistance, you can get in touch with us via Live Chat option by following- http://livechat.support.samsung.com/Customer_new/IN. You can also connect us via Samsung Members web community by following mentioned url-https://community.samsungmembers.com/en_IN#/
