How to adjust the height of the keyboard to the height of the button in the viber bot?

Question

Keyboard

Hello! How in Viber Bot to adjust (reduce) the height of the keyboard to the height of the only button that is 1 Rows? Is there some php line for this? By default, even one button is pressed to the top, and free space "walks" from the bottom and thus the useful part of the window with correspondence is blocked ... Thank you!

$message['keyboard'] = [
    "Type" => "keyboard",
    "DefaultHeight" => true,
    "Buttons" => [
    [
      "Columns" => 6,
      "Rows" => 1,
      ...

Answer 1

I added the code to the question and thus found a solution)

$message['keyboard'] = [
    "Type" => "keyboard",
    "DefaultHeight" => false,

false