i kept passcode and forgot it.how can i unlock it now?? p.s.:my find iphone is on.

Hello gamer_sabin,
Sorry to hear that you cannot access your iPhone because of not knowing the passcode, but this is something you can get passed.
The way to get passed this is to restore your iPhone. I know that it will erase the information on your iPhone, but if you have a recent back up in iTunes or iCloud, you can put that on after the restore completes. Take a look at the article below to walk you through restoring your iPhone with iTunes.
If you forgot the passcode for your iPhone, iPad, or iPod touch, or your device is disabled
https://support.apple.com/en-us/HT204306
Restore your device from an iCloud or iTunes backup
https://support.apple.com/en-us/HT204184
Take it easy