GUI with Slots (Linux,V: 2020.5)

I try to make an GUI for my "Refinerator" but as soon as i enable GUI with Slots the Buil Grade is failing
*Edited: This is a new Project with only the GUI and the only thing i edited was to set the gui to a gui with slots
*Edited2: Nothing from the forum i found helped
*Edited3: Happening with every Workspace
Log: 
Executing 
    Gradle task: build
Build 
    info: MCreator 2020.5.47520, forge-1.15.2, 64-bit, 3809 MB, Linux, JVM 
    1.8.0_265, JAVA_HOME: /home/Carslo45/.MCreator20205/jdk/jre
> 
    Configure project :
New 
    Dep: net.minecraftforge:forge:1.15.2-31.2.0_mapped_snapshot_20200514-1.15.1
> 
    Task :compileJava
/home/Carslo45/MCreatorWorkspaces/itdotu/src/main/java/carslo/mcmod/itdotu/gui/RefineratorMenuGui.java:176: 
    error: Override is not a repeatable annotation type 
 
         @Override
 
         ^
1 
    error
> 
    Task :compileJava FAILED
FAILURE: 
    Build failed with an exception.
* 
    What went wrong:
Execution 
    failed for task ':compileJava'.
> 
    Compilation failed; see the compiler error output for details.
* 
    Try:
Run 
    with --stacktrace option to get the stack trace. Run with --info or 
    --debug option to get more log output. Run with --scan to get full 
    insights.
* 
    Get more help at https://help.gradle.org
Deprecated 
    Gradle features were used in this build, making it incompatible with 
    Gradle 5.0.
Use 
    '--warning-mode all' to show the individual deprecation warnings.
See 
    https://docs.gradle.org/4.10.3/userguide/command_line_interface.html#se…
BUILD 
    FAILED in 10s
1 
    actionable task: 1 executed
BUILD 
    FAILED
Task 
    completed in 14243 milliseconds