If your iPad is disabled, or you have forgotten your iPad passcode, you’ll need to follow this process:
If you’ve forgotten the passcode on your iPad, or your iPad is disabled – Apple Support
You’ll need access to either a PC (with iTunes installed) or a Mac (with iTunes or Finder - as appropriate for the installed version of MacOS).
You’ll also need your AppleID and associated password. If these have also been forgotten, they can be recovered here:
https://iforgot.apple.com
To recover your credentials, you’ll need access to one of the following:
- Your primary email address mailbox that corresponds with your AppleID
- Any of the secondary/recovery email addresses that should be configured for your AppleID account
- Any of the trusted telephone numbers (fixed line or Cellular/Mobile) that are associated with your AppleID
Unless you AppleID account has not been fully/correctly configured, or has been seriously neglected, recovery of the AppleID and password should not be difficult.
More information about recovery of your AppleID:
If you forgot your Apple ID - Apple Support
More information about recovery of your AppleID password:
If you forgot your Apple ID password - Apple Support
When you recover access to your credentials, you would be well advised to log-in to your AppleID account from a web browser - and verify/update any email addresses and trusted telephone numbers:
https://appleid.apple.com
When you prepare your iPad for use by a new owner, you need to follow this process:
What to do before you sell, give away or trade in your iPhone, iPad or iPod touch – Apple Support
This procedure is crucial to ensure that all data is securely wiped - and that the Activation Lock that ties the device to the AppleID account is fully deactivated.
If, as I suspect you have done, you simply reset the iPad from Settings - and then deleted the device from your AppleID account - the Activation Lock that was created during the previous device activation remains intact. The “Hello” screen does not indicate that the Activation Lock has been removed - simply that the iPad is again in setup mode.
If my analysis is correct, your actions have actually made a relatively easy process - of “giving away” an iPad - significantly more complicated. The iPad is currently in a state whereby only you can resolve the problem; the iPad remains tied to your AppleID account.
Here are the Apple support pages that outline the Activation Lock - and the only mechanisms by which it can be turned off:
Activation Lock for iPhone, iPad, and iPod touch - Apple Support
Turn off Activation Lock – Apple Support
As you will discover, unless you are the owner of the AppleID that was last used to activate the device, or unless you can secure the cooperation of the previous owner (you), nobody else can defeat or bypass the Activation Lock.
I hope this information and insight proves to be helpful in resolving the problem. If you need more help, please ask - and I’ll try to provide additional guidance from where you get stuck.