Android API 24 < Crashes with java.lang.NoClassDefFoundError: com.google.common.base.CharMatcher

My app is crashing everytime it starts up with: java.lang.NoClassDefFoundError: com.google.common.base.CharMatcher. This only happens on devices running below android API 24. I have tried amending the Gradle versions and plugins as well as including the com.google.guava dependency but it did not work. Here is the full stack trace:

java.lang.NoClassDefFoundError: com.google.common.base.CharMatcher
at com.google.common.base.Splitter.on(Splitter.java:127)
at io.grpc.internal.GrpcUtil.<clinit>(GrpcUtil.java:197)
at io.grpc.internal.AbstractManagedChannelImplBuilder.<clinit>(AbstractManagedChannelImplBuilder.java:90)
at io.grpc.okhttp.OkHttpChannelProvider.builderForTarget(OkHttpChannelProvider.java:46)
at io.grpc.okhttp.OkHttpChannelProvider.builderForTarget(OkHttpChannelProvider.java:26)
at io.grpc.ManagedChannelBuilder.forTarget(ManagedChannelBuilder.java:76)
at com.google.firebase.firestore.remote.GrpcCallProvider.initChannel(GrpcCallProvider.java:113)
at com.google.firebase.firestore.remote.GrpcCallProvider.lambda$initChannelTask$6(GrpcCallProvider.java:256)
at com.google.firebase.firestore.remote.GrpcCallProvider$$Lambda$5.call(GrpcCallProvider.java)
at com.google.android.gms.tasks.zzy.run(com.google.android.gms:play-services-tasks@@17.1.0:2)
at com.google.firebase.firestore.util.ThrottledForwardingExecutor.lambda$execute$0(ThrottledForwardingExecutor.java:54)
at com.google.firebase.firestore.util.ThrottledForwardingExecutor$$Lambda$1.run(ThrottledForwardingExecutor.java)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)

I also get this exception constantly along with the above one:

W/System.err: io.reactivex.exceptions.UndeliverableException: java.lang.NoClassDefFoundError: io.grpc.okhttp.OkHttpChannelBuilder
at io.reactivex.plugins.RxJavaPlugins.onError(RxJavaPlugins.java:367)
at io.reactivex.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:69)
at io.reactivex.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:57)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:269)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1113)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:588)
at java.lang.Thread.run(Thread.java:818)
Caused by: java.lang.NoClassDefFoundError: io.grpc.okhttp.OkHttpChannelBuilder

My project level gradle file looks like this:

buildscript {
repositories {
google()
jcenter()
}
dependencies {
classpath 'com.google.gms:google-services:4.3.3'
classpath 'com.android.tools.build:gradle:4.0.2'
classpath "androidx.navigation:navigation-safe-args-gradle-plugin:2.3.0"
classpath 'com.google.firebase:firebase-crashlytics-gradle:2.1.1'
classpath 'com.google.firebase:perf-plugin:1.3.1'  // Performance Monitoring plugin
}
}
allprojects {
repositories {
google()
jcenter()
maven { url "https://jitpack.io" }
}
}

This is my app level gradle file:

plugins {
id("com.github.triplet.play") version "2.8.0"
}
apply plugin: 'com.android.application'
android {
compileSdkVersion 29
defaultConfig {
applicationId "..."
minSdkVersion 21
targetSdkVersion 29
versionCode 48
versionName "4.0.4"
testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
}
signingConfigs {
release {
...
}
}
buildTypes {
release {
signingConfig signingConfigs.release
minifyEnabled true
shrinkResources true
proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
}
debug {
minifyEnabled false
shrinkResources false
proguardFiles getDefaultProguardFile('proguard-android.txt'),
'proguard-rules.pro'
}
}
compileOptions {
sourceCompatibility JavaVersion.VERSION_1_8
targetCompatibility JavaVersion.VERSION_1_8
}
flavorDimensions "version"
productFlavors{
spanish{
dimension "version"
applicationId "..."
buildConfigField 'String', 'PRIMARY_COLOR', '"#ffc400"'
buildConfigField 'String', 'ACCENT_COLOR', '"#C60B1E"'
buildConfigField 'String', 'LANG_CODE', '"es"'
}
italian{
dimension "version"
applicationId "..."
buildConfigField 'String', 'PRIMARY_COLOR', '"#008C45"'
buildConfigField 'String', 'ACCENT_COLOR', '"#CD212A"'
buildConfigField 'String', 'LANG_CODE', '"it"'
}
}
packagingOptions {
exclude 'META-INF/DEPENDENCIES'
}
}
play {
...
}
dependencies {
//debugImplementation 'com.squareup.leakcanary:leakcanary-android:2.0-beta-5'
implementation fileTree(include: ['*.jar'], dir: 'libs')
implementation 'androidx.appcompat:appcompat:1.1.0'
implementation 'com.google.firebase:firebase-core:17.4.4'
implementation 'com.google.firebase:firebase-firestore:21.7.1'
implementation 'com.google.firebase:firebase-crashlytics:17.1.1'
implementation 'br.com.simplepass:loading-button-android:2.2.0'
implementation 'com.google.firebase:firebase-perf:19.0.8'
implementation 'com.google.firebase:firebase-analytics:17.4.4'
implementation 'com.google.firebase:firebase-functions:19.0.2'
implementation 'com.google.android.play:core:1.8.0'
implementation 'com.google.firebase:firebase-config:19.2.0'
implementation 'com.github.triplet.gradle:play-publisher:2.8.0'
implementation 'com.google.guava:guava:29.0-android'
}
apply plugin: 'com.google.gms.google-services'
apply plugin: 'com.google.firebase.crashlytics'
apply plugin: 'com.google.firebase.firebase-perf'

If you replace

implementation 'com.google.guava:guava:29.0-android'

for this

implementation ('com.google.guava:guava') {
version {
strictly '29.0-android'
}
}

it should work.