ERROR : invalid transaction termination : PostgreSQL v12

While reviewing the Transaction Management in PostgreSQL  "https://www.postgresql.org/docs/12/plpgsql-transactions.html" it speaks about a format which is not Supported. 

Transaction control is only possible in CALL or DO invocations from the top level or nested CALL or DO invocations without any other intervening command. For example, if the call stack is CALL proc1() → CALL proc2() → CALL proc3(), then the second and third procedures can perform transaction control actions. But if the call stack is CALL proc1() → SELECT func2() → CALL proc3(), then the last procedure cannot do transaction control, because of the SELECT in between. 

My Call has :  CALL Batch Job => SELECT function Used in SQL Statements  ==> Call Procedure.  We have transaction control in "CALL Batch Job" only. 

Pseudo Code is like : Highlighted in BOLD is a function call. It's failing when getting executed as we are using functions into this procedure.

We can't remove this function from the statement as its value is dependent on column value.

CREATE OR REPLACE PROCEDURE TEST_TRANSACTION(
)
LANGUAGE 'plpgsql'
    SECURITY DEFINER
AS $BODY$
DECLARE
    G_LAST_UPDATE_USER_SYSTEM VARCHAR2(6) := 'SYSTEM';
    G_LAST_UPDATE_MODULE_BATCH VARCHAR2(5) := 'BATCH';

    G_CNTR_LOADING_EXPIRED TMS_CONTAINER_LOADING.STATUS_CODE%TYPE := '90';
    G_DG_MANIFEST_DELETED TMS_DG_MANIFEST.STATUS_CODE%TYPE := '80';
    G_DG_MANIFEST_COMPLETED TMS_DG_MANIFEST.STATUS_CODE%TYPE := '95';

    v_num_day numeric;
    v_batch_count numeric;
    v_log_count numeric := 0;
    v_local_batch_count numeric;
BEGIN
        v_batch_count := 0;
        LOOP
            update tms_container_loading
               set status_code = G_CNTR_LOADING_EXPIRED
                 , last_update_tm = clock_timestamp()::timestamp(0)
                 , last_update_user_an = G_LAST_UPDATE_USER_SYSTEM
                 , last_update_module_code = G_LAST_UPDATE_MODULE_BATCH
             where tms$vvd.is_vessel_departed(vessel_visit_c,trunc(clock_timestamp()::timestamp(0))) = 1
               and coalesce(status_code,'~') <> G_CNTR_LOADING_EXPIRED  and ctid in (select a.ctid from tms_container_loading  where tms$vvd.is_vessel_departed(vessel_visit_c,trunc(clock_timestamp()::timestamp(0))) = 1
               and coalesce(status_code,'~') <> G_CNTR_LOADING_EXPIRED LIMIT 20000);
            EXIT WHEN NOT FOUND; /* apply on SQL */
            GET DIAGNOSTICS v_local_batch_count = ROW_COUNT; v_batch_count := v_batch_count + v_local_batch_count;
            COMMIT;
        END LOOP;
        v_log_count := v_log_count + 1; CALL Log(v_batch_count,'TMS_CONTAINER_LOADING',NULL, 'TMS$BATCH_JOB', v_log_count);
        COMMIT;
END;
$BODY$;