[Vuejs]-Fill with values – dynamic dropdowns

It sounds like a reactivity problem related to nested objects.

https://v2.vuejs.org/v2/guide/reactivity.html

Either sure your arrays are predefined within the getData object.

data () {
    return {
      getData: {
         field1 : [],
         field2 : []
      }
  }
},

Or update your getData object like this

this.$set(this.getData, key, this.takeServerData)