cannot be used to unlock this ipad how can sign in help me

Activation Lock?

http://support.apple.com/kb/TS4515

I am afraid you will need the Apple ID and Password of previous to activate iPad.

Then you are out of luck. Either return the stolen device to its rightful owner or discard it. You won't get in.

If by some slim chance the device is really yours, a trip to an Apple Store or an Authorized Service Center will be in order. Take legal proof that the device is yours.

help me please i cannot activate my ipad it says that "cannot be used to unlock this ipad" but the apple id and password is correct i also tried in icloud but i dont have find my ipad how is that i cant play my ipad for 3weeks plss help me my version on ios is 8.1.3