Using Vue, but I can't query information from Firebase to display values in a chart/graph (google charts or GChart). "Error: Table has no columns."

Question

This code is inside a .vue file. Receiving the "Error: Table has no columns." Inside the methods function, it won't receive the values from firebase to display a chart/graph to web app. What am I doing incorrectly? I think the values am I trying to receive inside "chartData:[ ]" or "mounted()" is incorrect and may be causing the issue. Any help is much appreciated.

    export default {
      name: "App",
      components: {
        GChart
      },
        methods: {
        
        getHumidity(){
                get(
                query(ref(db, auth.currentUser.uid + "/Environment/humidity"),
                  orderByChild("humidity")
                )
              ).then((snapshot) => {
                if (snapshot.exists()) {
                  console.log(snapshot.val());
                  for (const item in snapshot.val()) {
                    this.pgoods.push({
                      humidity: snapshot.val()[item].humidity,
                      expir: snapshot.val()[item].humidity,
                    });
                  }
                } else {
                  this.pgoods = [];
                }
                return float(snapshot.val());
              });
        }
    
    getPressure(){
                get(
                query(ref(db, auth.currentUser.uid + "/Environment/pressure"),
                  orderByChild("pressure")
                )
              ).then((snapshot) => {
                if (snapshot.exists()) {
                  console.log(snapshot.val());
                  for (const item in snapshot.val()) {
                    this.pgoods.push({
                      pressure: snapshot.val()[item].pressure,
                      expir: snapshot.val()[item].pressure,
                    });
                  }
                } else {
                  this.pgoods = [];
                }
                return float(snapshot.val());
              });
        }
    
    getTime(){
                get(
                query(ref(db, auth.currentUser.uid + "/Environment/time"),
                  orderByChild("time")
                )
              ).then((snapshot) => {
                if (snapshot.exists()) {
                  console.log(snapshot.val());
                  for (const item in snapshot.val()) {
                    this.pgoods.push({
                      time: snapshot.val()[item].time,
                      expir: snapshot.val()[item].time,
                    });
                  }
                } else {
                  this.pgoods = [];
                }
                return float(snapshot.val());
              });
        }, 
},

data(){
        return{
        chartData: [
                ["Time", "Pressure", "Humidity"],
                [this.getTime(), this.getPressure(), this.getHumidity()], 
                [this.getTime(), this.getPressure(), this.getHumidity()],
              ],
},
 mounted(){
    this.getTemperature();
    this.getHumidity();
  },
}