r.findIndex is not a function

[GustavoCarvalho]

What is the correct format I should pass to date = {?} ? And if it is an object like this: {"states_cidades": [      {        "acronym": "AC",        "name": "Acre",        "cities": [          "Acrelândia",          "Assis Brasil",          "Brasiléia",          "Bujari",          "Capixaba",          "Southern Cross",        ]      }}}

I would like to display only name in dropdown menu.

[mgroupservice]