sql – date_trunc month returning timestamp with timezone in Postgres

Initial table

id date
1  2021-01-01 00:00
2 2020-03-26 00:00
3 2019-05-16 00:00

The date datatype is text

I would like to change the date into month

id month
1 01/2021
2 03/2020
3 05/2019

The query I tried,

select id, date_trunc('month',date)::date as date_month
from schema.table t

ERROR: function date_trunc(unknown, text) does not exist
HINT: No function matches the given name and argument types. You might need to add explicit type casts.