error when the hologram is loaded about holoeasy HOT 5 CLOSED

public void updateTextLine(Hologram hologram) {
  /* You have four ways to manage lines:
   1) keep ILine<?>.
   2) cast ILine<?> to the ITextLine.
   3) cast directly to the implementation(impl could be TextLine, ClickableTextLine or TextALine).
   If you don't know the type you have the various getType and getEType methods of ILine interface.
  */
  ITextLine line = (ITextLine) hologram.getLines().get(0);

  // update the text.
  line.setObj("Updated");

  // now you need to update this hologram line for all seeing players of the hologram.
  line.update(hologram.getSeeingPlayers());
}