Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_21468 ( "Athlete" text, "Event" text, "Round of 64" text, "Round of 32" text, "Round of 16" text, "Quarterfinals" text )

### Question ###
What was round of 64 of the singles event when the result of round 16 was did not advance and the athlete was Iveta Bene ov ?

### Accurate SQL ###

SELECT "Round of 64" FROM table_21468 WHERE "Event" = 'Singles' AND "Round of 16" = 'Did not advance' AND "Athlete" = 'Iveta Benešová'