Vuex - Computed property "name" was assigned to but it has no setter

For me it was changing.

this.name = response.data;

To what computed returns so;

this.$store.state.name = response.data;

It should be like this.

In your Component

computed: {
        ...mapGetters({
                nameFromStore: 'name'
            }),
        name: {
           get(){
             return this.nameFromStore
           },
           set(newName){
             return newName
           } 
        }
    }

In your store

export const store = new Vuex.Store({
         state:{
             name : "Stackoverflow"
         },
         getters: {
                 name: (state) => {
                     return state.name;
                 }
         }
}

If you're going to v-model a computed, it needs a setter. Whatever you want it to do with the updated value (probably write it to the $store, considering that's what your getter pulls it from) you do in the setter.

If writing it back to the store happens via form submission, you don't want to v-model, you just want to set :value.

If you want to have an intermediate state, where it's saved somewhere but doesn't overwrite the source in the $store until form submission, you'll need to create such a data item.