timestampz column not queryable in function - postgresql

Question

I have a function call like :
SELECT * FROM f_loop_in_lockstep_final('{454,454}'::int[]
, '{2,3}'::int[], to_date('2023-01-17','YYYY-MM-DD'));
I have declared funtion as :
CREATE or replace FUNCTION f_loop_in_lockstep_final(_id_arr int[], _counter_arr int[], d_date date)
In the function body I have written the following where clause (simplified):
select * from routes where
routes.time_created between ((d_date::date + '11:59:00'::time) at time zone '+05:00') and ((d_date::date + '18:00:00'::time) at time zone '+05:00')
This is giving a null result set (although no errors are displayed), whereas I know for sure that it should be non null result set.
P.S - Here is the simplified code of my function:
CREATE or replace FUNCTION f_loop_in_lockstep_final(_id_arr int[], _counter_arr int[], d_date date)
RETURNS TABLE (uc_name_ varchar)
LANGUAGE plpgsql AS
$func$
DECLARE
_id int;
_counter int;
d_date date;
BEGIN
FOR _id, _counter IN
SELECT *
FROM unnest (_id_arr, _counter_arr) t
LOOP
RETURN QUERY
with orig_dataset as (
select routes
from campaign_routes cr
where cr.created_at between ((d_date::date + '11:59:00'::time) at time zone '+05:00') and ((d_date::date + '18:00:00'::time) at time zone '+05:00')
)
-- a couple of further CTE's result in a final CTE called final_cte
select * from final_cte;
END LOOP;
END
$func$;