Qwerty keyboard is showing on Oppo, when it should be a numerical keyboard

Question

My EditText has an inputType="numberPassword"and I've tested this on many devices and it shows correctly (a numerical keyboard), BUT on an Oppo device it just shows a qwerty keyboard.

<EditText
            android:id="@+id/dit_text"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:enabled="false"
            android:hint="@string/pin_login"
            android:inputType="numberPassword"
            android:letterSpacing="0.2"
            android:maxLength="4" />

How can I solve this?