maven multi-module project not running

Question

I have developed a multi-module project with Java spring boot on IntelliJ. This is runnable in the IDE without any problem via 'run Application' where 'Application' is my SpringBootApplication and located in a submodule of the parent module.

Now I want to run this system on a server and I am unable to get it running. I tried

mvn spring-boot:run

and I get following error:

Error: Could not find or load main class com.example.application.Application Caused by: java.lang.ClassNotFoundException: com.example.application.Application

I also tried other commands like

mvn clean package

where I get errors saying that packages from the 'shared_model' (succesfully compiled - because no dependencies of other modules) do not exist (although they exist), while trying to compile 'aggregate'-package (depending on 'shared_model'), e.g.:

[ERROR] /.../aggregates/src/main/java/com/example/aggregates/.../.java:[3,52] package com.example.shared_model.... does not exist

[ERROR] /.../aggregates/src/main/java/com/example/aggregates/.../.java:[13,12] cannot find symbol

The file structure looks like this:

main
├── adapters-input
├── adapters-output
├── aggregates
├── application
├── application-services
└── shared_model

Where every package has its own pom-file.

The pom of the parent module looks as follows:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>main</artifactId>
    <packaging>pom</packaging>
    <version>0.0.1-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <properties>
        <java-version>11</java-version>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
    </properties>
    <modules>
        <module>adapters-output</module>
        <module>adapters-input</module>
        <module>application-services</module>
        <module>aggregates</module>
        <module>application</module> <!-- location of main class -->
        <module>shared_model</module>
    </modules>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <mainClass>com.example.application.Application</mainClass>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

The pom of the 'application'-package looks as follows:

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.6.1</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>application</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>
    <name>application</name>
    <description>Application endpoint</description>
    <properties>
        <java.version>11</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>com.example</groupId>
            <artifactId>adapters-input</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>shared_model</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>adapters-output</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>application-services</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>com.example</groupId>
            <artifactId>aggregates</artifactId>
            <version>0.0.1-SNAPSHOT</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
    </dependencies>

</project>

I tried a lot of things and became a little desperate. It seems like there is an issue with seeing sibling-modules and child-modules, but I don't see why. Also, I don't understand why it is working smoothly from when ran from IntelliJ.

I greatly appreciate any help. Thanks!