Why I cannot persist plugin settings (project scope)?

I've created custom PropertiesComponent based on PropertiesComponentImpl.

The differences:

@State(
        name = "TaskTimer",
        storages = {@Storage(StoragePathMacros.WORKSPACE_FILE)}
)

above class declaraton and:

public void setTogglToken(String token) {
    this.setValue("ttoken", token);
}

public String getTogglToken() {
    return this.getValue("ttoken");
}

public void setTogglProject(String name) {
    this.setValue("tproject", name);
}

public String getTogglProject() {
    return this.getValue("tproject");
}

@NotNull
public String getComponentName() {
    return "TaskTimer";
}

inside class. That's all differences from example implementation.

My Configurable implementation:

private final TaskTimerPropertiesComponent properties = new TaskTimerPropertiesComponent();

@Override
public void apply() throws ConfigurationException {
    properties.setTogglToken(token.getText());
    properties.setTogglProject(projectsList.getSelectedItem().toString());
}

but in createComponent() method getters returns always nulls, so it seems that those values weren't persisted after closing settings window.

What am I doing wrong here?