I'm sorry about the issue, the only solution is to restore your iPad devic which will cause you to lose all data (photos, files, ect...) currently on device. If you made a backup (eg : iCloud) prior to losing the password, you should be able to recover that.
Here are the steps to restore your iPad :
1-Download Itunes from : https://www.apple.com/itunes/download/
2-Install itunes and plug in your iPad to your pc or mac
3-press and hold the home button and the sleep/wake/power button at the same time for 45 seconds until the Apple logo appears, once that appears you can release the buttons
4-iTunes will give message iTunes has detected an iPad in recovery mode you must restore this iPad to continue
5-click restore if it does not go through click on the iPad in the left hand side of iTunes and click restore
6-restore iPad and now you should have your iPad back.
Additional Information : https://www.youtube.com/watch?v=Shrc3FeCJEQ
Let me know the results please