Error - cannot access io.reactivex.Observable about rxjavafx HOT 1 CLOSED

plugins {
id 'java'
id 'application'
id 'org.openjfx.javafxplugin' version '0.0.9'
}

group 'org.example'
version '1.0-SNAPSHOT'

repositories {
mavenCentral()
}

dependencies {
implementation 'io.reactivex.rxjava3:rxjava:3.0.13-RC2'
implementation 'io.reactivex.rxjava2:rxjavafx:2.2.2'
// https://mvnrepository.com/artifact/io.reactivex.rxjava2/rxjava
implementation group: 'io.reactivex.rxjava2', name: 'rxjava', version: '2.2.2'

implementation("com.google.guava:guava:30.1.1-jre")
testCompile group: 'junit', name: 'junit', version: '4.12'
}

javafx {
version = "16"
modules = [ 'javafx.controls', 'javafx.fxml' ]
}