Hi and Welcome. My Name is Ashik and I look forward to assisting you today with your question.
This usually happens if your Notes application syncs with your Email account or iCloud
. Although its great to sync with the Email or iCloud, it does't work always as expected. This has happened to me also. So I disabled syncing the Notes with my email account and that fixed it for me.
On your iPad, goto Settings, tap Mail, Contacts, Calenders. Select your Email account in there, and turn off Notes. That should fix the problem.
For missing notes, open your email account on your computer and see if you can find a folder named "Notes" on it, it should be under Inbox, Sent, Drafts etc
I'd recommend to backup all of your Notes (email them to yourself) before turning of Notes in Mail, Contacts, Calenders.
And In my opinion, Notes application is not very reliable. So I use Evernote app from AppStore instead of Notes. You should try that. See here : https://itunes.apple.com/in/app/evernote/id281796108?mt=8
If you've any questions or would like any additional information, please don't hesitate to ask.
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