Q: this serial number is associated to another Apple ID

Just from whom did you purchase the device?

Where did you purchase it? Did you purchase it from an Apple Store?

Cheers,

GB

Sorry, but if it was not purchased from an Apple Store or an Authorized Apple Reseller, and you are running into the Activation Lock, then it was not a new device. Sealing the package is a common practice when someone is selling a stolen phone.

Sorry, but you won't be able to use the device. Get your money back if you can.

Best of luck,

GB

The fact that it is registered to someone else is not going to affect its performance. Sorry - I mistakenly said it was Activation Lock above, but its not. It may also be Activation Locked which will render the device useless if you ever have to restore it, but it is highly unlikely that it is actually a new device.

Best of luck,

GB