c++ Inserting to Queue in Array using Arrow Operator

Question

I'm working on a project that simulates a line at a grocery store. There are several cashiers and I need the program to determine which cashier has the shortest line and insert an asterisk representing a customer into that cashier's queue. Right now I have my individual cashier queues in an array called "cashiers". What I'm currently stuck on is being able to insert to my individual cashier's queues. By calling: cashiers->getShortestLine() I am able to get the cashier's name, but unable to call a successful insert. I'm not getting an error message; the insert call doesn't appear to be working (the cashier with the shortest queue isn't receiving another asterisk-customer). I'll post my code below. In this example, cashier Burt has the shortest line, but getting the program to automatically insert a new "customer" to the shortest line does not seem to be working.

Let me know if I can provide more info and thanks so much for any help.

#include <iostream>
#include <vector>
#include <string>
using namespace std;

class Queue{ 
    private:
        int maxSize;
        vector<char> vecQueue;
        string name;
        char front;
        char rear;
        int nItems;
    public:
        Queue(int max, string n) : maxSize(max), name(n), front(0), rear(-1), nItems(0){
            vecQueue.resize(maxSize);
        }

        void insert(char c){
            if(rear == maxSize-1){
                rear = -1;
            }
            vecQueue[++rear] = c;
            nItems++;
        }

        char remove(){                 //take item from front of queue
            char temp = vecQueue[front++];  //get value and incr front
            if(front == maxSize)          //deal with wraparound
                front = 0;
            nItems--;                     //one less item
            return temp;
      }

        bool isEmpty(){
            return (nItems == 0);
        }

        int numItems(){
            return nItems;
        }

        string getName(){
            return name;
        }

        Queue getShortestLine(){
            Queue smallest = this[0];
            for(int i = 0; i < 9; i++){
                if(smallest.numItems() > this[i].numItems()){
                    smallest = this[i];
                }
        }
        cout << "Shortest Line: " << smallest.getName() << endl;
        return smallest;
        }

        Queue getLongestLine(){
            Queue longest = this[0];
            for(int i = 0; i < 9; i++){
                if(longest.numItems() < this[i].numItems()){
                    longest = this[i];
                }
        }
        cout << "Longest Line: " << longest.getName() << endl;
        return longest;
        }

        void displayCashiers(){
        for(int i = 0; i < 9; i++){
        cout << this[i].getName() << ": "; 
        for(int j=0;j<this[i].numItems();j++){cout << "*";} 
        cout << endl;
    }
    cout << endl;
        }


};

int main(){
    char star = '*';

    Queue cashierAbigail(100, "Abigail");
    Queue cashierBurt(100, "Burt");
    Queue cashierCaitlin(100, "Caitlin");
    Queue cashierDylan(100, "Dylan");
    Queue cashierEmily(100, "Emily");
    Queue cashierFrank(100, "Frank");
    Queue cashierGerald(100, "Gerald");
    Queue cashierHeather(100, "Heather");
    Queue cashierIsaac(100, "Isaac");

//Cashier Abigail
    cashierAbigail.insert(star);
    cashierAbigail.insert(star);
    cashierAbigail.insert(star);

//Cashier Burt
    cashierBurt.insert(star);
    cashierBurt.insert(star);

//Cashier Caitlin
    cashierCaitlin.insert(star);
    cashierCaitlin.insert(star);
    cashierCaitlin.insert(star);

//Cashier Dylan
    cashierDylan.insert(star);
    cashierDylan.insert(star);
    cashierDylan.insert(star);

//Cashier Emily
    cashierEmily.insert(star);
    cashierEmily.insert(star);
    cashierEmily.insert(star);

//Cashier Frank
    cashierFrank.insert(star);
    cashierFrank.insert(star);
    cashierFrank.insert(star);

//Cashier Gerald
    cashierGerald.insert(star);
    cashierGerald.insert(star);
    cashierGerald.insert(star);
    cashierGerald.insert(star);

//Cashier Heather
    cashierHeather.insert(star);
    cashierHeather.insert(star);
    cashierHeather.insert(star);

//Cashier Isaac
    cashierIsaac.insert(star);
    cashierIsaac.insert(star);
    cashierIsaac.insert(star);
    


    Queue cashiers[9] = {
        cashierAbigail,
        cashierBurt,
        cashierCaitlin,
        cashierDylan,
        cashierEmily,
        cashierFrank,
        cashierGerald,
        cashierHeather,
        cashierIsaac
    };
    

    cashiers->displayCashiers();
    cashiers->getShortestLine().insert(star);
    cashiers->displayCashiers();
    

    return 0;
}