Being able to re-activate/re-verify-ing this 12-year old iPad may no longer ever be possible,,now, in 2022.
Sorry.
Sometime in mid 2021, Apple made changes to its activation servers that now check device activation validation through the Safari Web browser, now.
If you had been using that over 5-year old Safari Web browser to accesss the Internet, I suspect that this was the reason your old, 10-1/2-year old, 2011 iPad 2 went into user activation mode.
That old Safari Web browser is over 5-years old, now, and is NOT safe and secure to use to accesss the Internet, any longer.
I, also, suspect with this new device activation method, that old Safari Web browser may no longer be able to negotiate getting by Apple's new activation authentication server processes/protocols and allowing that old iPad to be re-activated.
I, also, suspect that Apple didi this to silently and permanently end use of these over 9-10-year old iPad models on their networks, pretty much completely ending the use of these very old iOS devices.
Apple's own procedures, my own procedures, as well as those from others, may no longer be effective to re-activate these very old iPad models.
You need to realise that the iPad 1, 2, 3, 4 and 1st gen iPad Mini are all very old and obsolete, now.
Sorry.
Apple ended support for all 9-12-year old iOS devices nearly 5 years, ago, in 2016.
Apple ended support for the 2010, 1st gen iPad in 2012!
Third party app developers abandoned and stopped supporting these 9-12year old iOS devices nearly 3 years, ago, in 2018.
There are, virtually, NO MORE third party apps available from the iOS App Store, any longer!
Third party compatible apps for such old devices are few and far between, now, in 2022.
This includes apps for iOS 5, iOS 9 AND iOS 10 devices and, throughout 2022, ALL iOS 12 ONLY devices!
AND, NO WAY to, initially, install any older, compatible, third party apps into this old iPad, any longer!
NO MORE SUPPORT! NO MORE APPS!
All 2010-2012 iPad 1, 2, 3, 4 and 1st gen iPad Mini models are fully and completely unsupported AND obsolete!
Sorry, but this is the reality for ALL 9-11-year old AND OLDER iOS devices now. Especially now, in 2022.
In addition, the internal, rechargeable batteries in these old iPads are, also, running on borrowed time.
Not worth the costs to replace these old internal, rechargeable batteries in these old iPads, any longer, either.
It's 2022, now.
A WHOLE LOT has happened with iPad in 12 years.
You really need to seriously consider a purchase of a new iPad model OR a much, MUCH “newer” and less expensive, refurbished or used iPad models, from better known, trusted Apple product/device retailers/resellers, some locally or from online, on the Web/Internet, capable of running the latest iPadOS versions.
There are PLENTY of less expensive, newer, older iPad models that can run the latest, current versions of iPadOS.
If you need OR ONLY able to purchase older, less expensive iPad models, look at older iPads from 2014 and later.
All of these older model iPads below, CAN, currently, run the latest releases of iPadOS 15.
2014, 9,7 inch screen iPad Air 2 models ( NO Pencil support )
2015, 7.9 inch screen iPad Mini 4 models ( NO Pencil support )
2015-2017, 12.9 inch screen iPad Pro models. ( 1st gen Pencil support )
2016, 9.7 inch screen iPad Pro models ( 1st gen Pencil support )
2017,10.5 inch screen iPad iPad Pro models ( 1st gen Pencil support )
2017, 9.7 inch screen iPad 5th gen models ( NO Pencil support )
2018, 9.7 inch screen iPad 6th gen models ( 1st gen Pencil support )
2019, 10.2 inch screen iPad 7th gen models ( 1st gen Pencil support )
2020, 10.2 inch screen iPad 8th gen models. ( 1st gen Pencil support )
2019, 7.9 inch screen iPad Mini 5th gen models ( 1st gen Pencil support )
Get the largest internal data storage model you can afford as NO Apple iOS device has ANY expandable storage.
I am sorry that you had to learn all of this, but this does not change any of the facts regarding these very old iOS devices.
Please recycle these old devices properly and responsibly.
Sorry & Best of Luck to You!