Activation Lock

When prompting for the AppleID, it should provide a clue - something like first and last characters with asterisks to indicate hidden letters. Usually, this will be enough of a hint to identify the primary email address that corresponds with the AppleID.

When you’ve worked-out the AppleID used to previously activate the iPad, if the password has been forgotten, it can be recovered here:

https://iforgot.apple.com

Even if you have discarded or forgotten the primary email address, you should still be able to receive reset information via one of the secondary/recovery email addresses that you should have created for your AppleID account - or any one of the trusted contact telephone numbers also associated with the AppleID account.

When you have both the AppleID and associated password, you can either use these to release the Activation Lock by entering these details on the device - or you can log-in to your AppleID account and remove the Activation Lock from within the AppleID account pages:

https://appleid.apple.com

Whilst logged-in to the account from a browser, it’s a golden opportunity to verify/update your primary and multiple secondary/recovery email addresses, together with a selection of trusted contact telephone numbers (both fixed line and mobile/cellular numbers are a good idea). Always remember - your AppleID account is the key to everything.

Here is some additional information about the Activation Lock and associated procedures:

https://support.apple.com/en-us/HT201365

I hope this information will provide multiple avenues with which to find a route to resolution of your problem.

It's locked to a different Apple ID. You need to log in with that one, or contact the person who can, or if you're the iPad's original owner, supply Apple with its purchase receipt.

(180245)

You may have enabled Apple Mail in your iCloud settings - which will provide an Apple email address.

Provided that you have configured (at least one) secondary/recovery email address - or (at least one) trusted telephone number - you should be able to recover access to the associated AppleID account. Once you have access to the account, this being the key to all your Apple services, you should be able to resolve any other issues and/or device Activation Locks.

All the steps that I suggested can be completed from any web browser.

Until you resolve any issues you may have with your AppleID credentials, you’re not going to be able to pass the Activation Lock on your iPad. Your iPad is currently locked and unusable. Your AppleID is the key to making progress.