Hm, I need more info please and where did you get the Alien Core from?
you mean EU?
What happened exactly? You dismantled the Alien Core with your Multi tool?
Did you read the Guide about the Alien Core?
WARNING: if you dismantle an Alien Core it will become parts in your inventory. You CAN’T get the Alien Core back out of your structure unless you have EGS Recycle level 5 and recycle your structures!