export 'extend' was not found in 'vee-validate'

[arishojaei]

I created a file in plugins and added it to nuxt.config but I get export 'extend' was not found in 'vee-validate'

// ~/plugins/validate.js

import { extend } from 'vee-validate'

extend('postCode', (value) => {
  const reg = /^\d+$/
  if (value.length === 10 && reg.test(value)) {
    return true
  }
  return "{_field_}"
})