ThingsBoard, custom chart widget data

I have a hierarchy widget that broadcasts an event with the node selected.

The hierarchy widget is something like this:

Group 1

• device 1
• device 2
• device 3

Group 2

• device 1
• device 2
• device 3

The chart will initially show timeseries data for devices in Group 1.

When Group 2 is selected, I want the chart to show timeseries for devices in Group 2.

So, my chart widget captures the event with the group id and then tries to define a new datasource and makes the subscription:

self.onInit = function() {
    self.ctx.$scope.timeSeriesChartWidget.onInit();

    let $scope = self.ctx.$scope;
    self.ctx.broadcastService = $scope.$injector.get(self.ctx.servicesMap.get('broadcastService'));

    self.ctx.broadcastService.on('change-graph', function(event, args) {
        const receivedData = args[0];
        const groupId = receivedData.groupId;
        const groupName = receivedData.groupName;

        console.log('PSI Line Chart received "change-graph" for Group:', groupName, 'ID:', groupId);


        if (!groupId) {
            console.warn('Received "change-graph" broadcast but groupId is undefined. Chart will not update.');
            return;
        }

        const datasources = [
            {
                type: 'entity',
                dataKeys: [
                    {
                        name: 'psi',
                        type: 'timeseries',
                        label: 'Pressure',
                        settings: {}
                    }
                ],
                entityFilter: {
                    type: 'relationsQuery',
                    rootEntity: {
                        id: groupId,
                        entityType: 'ASSET'
                    },
                    direction: 'FROM',
                    maxLevel: 1,
                    fetchLastLevelOnly: false,
                    filters: [
                        {
                            relationType: "Contains",
                            entityTypes: [
                                "DEVICE"
                            ]
                        }
                    ]                   
                }
            }
        ];
        
        const subscriptionOptions = { 
            type: 'timeseries', // Subscription type
            singleEntity: false,
            datasources: datasources, // Describes what data you want to subscribe
            ignoreDataUpdateOnIntervalTick: true, //if true onDataUpdated will be triggered only when new data appears otherwise onDataUpdate will be triggered every second
            useDashboardTimewindow: true,
            callbacks: {
                onDataUpdated: () => {
                    self.onDataUpdated();
                },
            },
        };
        

        self.ctx.subscriptionApi.createSubscription(subscriptionOptions, true).subscribe(
            (subscription) => {
                //Data is not available here! Code below just indicates where data will save.
                self.ctx.defaultSubscription = subscription; //Saves subscription information into widget context
                self.ctx.data = subscription.data; //Saves data into widget context
                self.ctx.datasources = subscription.datasources; //Saves datasource into widget context
            }
        ); 


    });

    const defaultGrupo1Id = '0a2f8e60-6959-11f0-899a-b775ed58e7c9'; // Your actual Grupo 1 ID

    self.ctx.broadcastService.broadcast('change-graph', {
        groupId: defaultGrupo1Id,
        groupName: 'Grupo 1'
    });

};

The problem is that data is empty, so chart does not show lines.