Android Studio – Image view not showing after scrollview

I am creating simple Android application where user can read lyrics while listening song.
My problem is in inside android activity.
After ScrollView there are 3 imageViews inside linearLayout these are my play,pause and stop images which are not showing
what am i doing wrong?

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#DFC3C3"
    tools:context=".FirstSong"
    android:orientation="vertical">

        <TextView
            android:id="@+id/textView4"
            android:layout_width="match_parent"
            android:layout_height="40dp"
            android:layout_marginTop="16dp"
            android:layout_marginBottom="13dp"
            android:background="@drawable/ic_button_brown_pink"
            android:gravity="center"
            android:text="@string/firstSongTitle"
            android:textColor="#26358A"
            android:textSize="28sp"
            android:textStyle="bold"
           />


    <ScrollView
        android:id="@+id/scrollView4"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_marginBottom="20dp"
       >

        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="300dp"
            android:orientation="vertical">

            <TextView
                android:id="@+id/txtTextView"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:layout_gravity="center_horizontal"
                android:layout_marginTop="36dp"
                android:gravity="center"
                android:text=""
                android:textAlignment="center"
                android:textColor="#094F59"
                android:textSize="17sp"
                android:textStyle="bold" />

        </LinearLayout>
    </ScrollView>



    <LinearLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"

        android:layout_gravity="center"
        android:orientation="horizontal">

        <ImageView
            android:id="@+id/imageplay"
            android:layout_width="61dp"
            android:layout_height="34dp"
            app:srcCompat="@drawable/ic_green1playbutton"
            tools:layout_editor_absoluteX="102dp"
            tools:layout_editor_absoluteY="651dp" />

        <ImageView
            android:id="@+id/imagepause"
            android:layout_width="61dp"
            android:layout_height="34dp"
            app:srcCompat="@drawable/ic_green1pausebutton"
            tools:layout_editor_absoluteX="173dp"
            tools:layout_editor_absoluteY="651dp" />

        <ImageView
            android:id="@+id/imagestop"
            android:layout_width="61dp"
            android:layout_height="34dp"
            app:srcCompat="@drawable/ic_green1stopbutton"
            tools:layout_editor_absoluteX="234dp"
            tools:layout_editor_absoluteY="651dp" />

    </LinearLayout>



    </LinearLayout>

By the way i’am new to Android Studio