Android : Android: text button disordered and cut when more than 1 line

I am having a problem with text in a button. When the text is more than one line, the size of the button is shortened from above and the text does not appear in the center and cut the bottom.

What can be my problem?

xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/linear_botones"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal" >

<Button
    android:id="@+id/boton_monumento_1"
    android:layout_width="100dp"
    android:layout_height="45dp"
    android:layout_marginRight="1dp"
    style="@style/botonMonumentos" />

<Button
    android:id="@+id/boton_monumento_2"
    android:layout_width="100dp"
    android:layout_height="45dp"
    android:layout_marginRight="1dp"
    style="@style/botonMonumentos" />

</LinearLayout>

styles

<style name="botonMonumentos">
    <item name="android:textSize">13sp</item>
    <item name="android:ellipsize">end</item>
    <item name="android:gravity">center</item>
    <item name="android:maxLines">2</item>
</style>