To fix push to Vuex store array not working in Vue, we commit a mutation.

For instance, we write

const store = new Vuex.Store({
  state: {
    customers: [{ id: "1", name: "user 1" }],
  },
  mutations: {
    addCustomer: (state, customer) => {
      state.customers.push(customer);
    },
  },
})

to define our Vuex store with the addCustomer mutation.

In it, we call state.customers.push to append customer as the last item of the customers state.

Then we write

store.commit("addCustomer", { id: "2", name: "User 2" });

to call store.commit with the name of the mutation to commit and the object we want to append to the state.