[Vuejs]-Vuetify date picker doesn't save the correct date if i type it in my text field

try using :value on text-field

<v-text-field :value="date">

then using vue filters.. you can check the documentation how to use it here.
https://v2.vuejs.org/v2/guide/filters.html

and then add filter at you value. for example :value="date | formatDate"
i hope it helps.