script help

//i need help with this script the issue is that when i rez this item for the first time it does what its suppose to do but if i take it and rez it somewhere else in the sim it return to the original 1st time rez place how do i remove it?

integer target;
vector offset = <0.0,0.0,2.0>;
vector tpos;
float speed = 1.0;
default
{
    state_entry()
    {

        tpos = llGetPos() + offset;
        target = llTarget(tpos,0.01);
        llSetStatus(STATUS_PHYSICS|STATUS_PHANTOM,TRUE);
        llSetStatus(STATUS_ROTATE_X|STATUS_ROTATE_Y|STATUS_ROTATE_Z,FALSE);
        llMoveToTarget(llGetPos() + offset,llVecDist(llGetPos(), tpos)*speed);
    }



    at_target(integer tnum,vector targetpos, vector mypos)
    {

        llTargetRemove(target);
        llStopMoveToTarget();
        offset = -offset;
        tpos = llGetPos() + offset;
        target = llTarget(tpos,0.01);
        llMoveToTarget(tpos,llVecDist(llGetPos(), tpos)*speed);
    }

    not_at_target()
    {
        llMoveToTarget(tpos,llVecDist(llGetPos(), tpos)*speed);
    }
}