How to Convert string to date

How to Convert string to date

Hi,
I need to create a formula to convert string in datetime in zoho reports, so I've created a query to isolate this values, and now I need to convert it.  I'm trying to build a formula but a mensagem shows up, saying that I'm not using an aggregate function.

Formula:
convert_string_to_date("Nova Tabela de Consulta"."DATA CONVERTIDA ",'%d %m %Y')

Table : "Nova Tabela de Consulta"
Column: "DATA CONVERTIDA"