Restrictions password reset
Recently I have forgotten my restrictions password. Due to to this I was unable to install some apps from appstore.
iPad mini, iOS 9
From the article below.
If you can't remember a restrictions passcode that you created on a previous version of iOS, or you forgot your Screen
Time passcode, you need to erase your device, then set it up as new to remove the passcode. Restoring your device won't remove your old passcode.
Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support
You will need to restore the device to factory settings. Do not restore from a backup made when the Screen Time code was active.
Restore to Factory setting. https://support.apple.com/en-us/HT201252
Backup - Restore your device from an iCloud or iTunes backup. https://support.apple.com/en-us/HT204184