You will have to Delete & Reinstall the app.

To Delete the OneDrive App
  • Tap Settings on the iPad
  • Tap General
  • Tap iPad Storage
  • Tap on OneDrive icon
  • Tap on Delete App

To Bring it back
  • Go to the icon that is a Blue and says Secure Hub Open it.
  • Tap Menu on the upper right.
  • Select Preferences
  • Select Device Information
  • Select Refresh Policy
  • Wait for the app to appear (About 5 minutes)