If a power cycle won't work then plug it into your computer and back it up. After it backs up press and hold power and home button until the unit turns off, continue to hold it for 15 seconds. Screen should stay off but now your de ice is in DFU mode. This will allow you to restore the device to stock settings. Now you can reload whats important or sell it and buy one that has more storage and restore the backup you made to it. Biggest problem with apple is lack of storage upgrades. If you dont buy large enough first time around you're screwed.
I always look on YouTube it's full of answers that are relevant and helpful. Call Apple care they will help you even if your iPad is out of warranty. I was just there and my computer has been out of warranty for several years great customer support
Turn it off then turn it back on if u still have problems take it to the store u bought it from
Take it to the apple store. A technician can help u solve the problem better then anyone. Another option is the geek squad at best buy. Hope this helps
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