سلام وقت بخیر 

احساس میکنم شما margin یا padding برای لیوتتون (که احتمالا میتونه لینیر لیوت باشه ) مشخص کردید. و مشکل از button نیست.

در غیر این صورت کد کامل xml مربوطه رو کپی کنید تا بررسی بشه.

خیر من margin , padding تعریف نکردم

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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="@color/gray100"
    tools:context=".ProfileActivity">
    <TextView
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="56dp"
        android:elevation="500dp"
        android:fontFamily="sans-serif-medium"
        android:gravity="center_vertical"
        android:paddingStart="12dp"
        android:paddingEnd="0dp"
        android:text="@string/app_name"
        android:textColor="@color/black"
        android:textSize="14sp" />
    <Button
        android:id="@+id/save_info_btn"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:backgroundTint="@color/blue"
        android:text="@string/save_btn"
        android:textColor="@color/white"
        android:textStyle="bold" />
    <ScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@+id/save_info_btn"
        android:layout_below="@id/toolbar"
        android:id="@+id/scroll">
        <androidx.constraintlayout.widget.ConstraintLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <ImageView
                android:id="@+id/imageView2"
                android:layout_width="100dp"
                android:layout_height="100dp"
                android:layout_marginTop="24dp"
                android:contentDescription="@string/profile_photo_text"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toTopOf="parent"
                app:srcCompat="@drawable/user_photo" />
            <TextView
                android:id="@+id/textView4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="5dp"
                android:textColor="@color/black"
                android:textSize="14sp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/imageView2"
                tools:text="Amir Hossein Parandin" />
            <Button
                android:id="@+id/button"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginEnd="5dp"
                android:backgroundTint="@color/blue"
                android:text="@string/edith_profile_btn"
                android:textColor="@color/white"
                app:cornerRadius="5dp"
                app:layout_constraintEnd_toStartOf="@+id/button2"
                app:layout_constraintHorizontal_bias="0.5"
                app:layout_constraintHorizontal_chainStyle="packed"
                app:layout_constraintStart_toStartOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/textView4" />
            <Button
                android:id="@+id/button2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginStart="5dp"
                android:text="@string/view_website_btn"
                android:textColor="@color/blue"
                app:cornerRadius="5dp"
                app:layout_constraintEnd_toEndOf="parent"
                app:layout_constraintHorizontal_bias="0.5"
                app:layout_constraintStart_toEndOf="@+id/button"
                app:layout_constraintTop_toTopOf="@+id/button"
                app:strokeColor="@color/blue"
                app:strokeWidth="1dp" />
            <androidx.constraintlayout.widget.Guideline
                android:id="@+id/guideline"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:orientation="vertical"
                app:layout_constraintGuide_begin="24dp" />
            <TextView
                android:id="@+id/textView6"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:fontFamily="sans-serif-medium"
                android:text="@string/skills_text"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/button" />
            <TextView
                android:id="@+id/textView7"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:fontFamily="sans-serif-medium"
                android:text="@string/city"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/checkBox4" />
            <CheckBox
                android:id="@+id/checkBox"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:text="@string/skill_android"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/textView6" />
            <CheckBox
                android:id="@+id/checkBox3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/skill_uiDesign"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/checkBox" />
            <CheckBox
                android:id="@+id/checkBox4"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/skill_web"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/checkBox3" />
            <RadioButton
                android:id="@+id/radioButton"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginTop="8dp"
                android:text="@string/city_eslamAbad"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/textView7" />
            <RadioButton
                android:id="@+id/radioButton2"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/city_gilan"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/radioButton" />
            <RadioButton
                android:id="@+id/radioButton3"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="@string/city_kermanshah"
                app:layout_constraintStart_toStartOf="@+id/guideline"
                app:layout_constraintTop_toBottomOf="@+id/radioButton2" />
        </androidx.constraintlayout.widget.ConstraintLayout>
    </ScrollView>
</RelativeLayout>