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_21687 ( "Athlete" text, "Event" text, "Round of 32" text, "Round of 16" text, "Quarterfinals" text, "Semifinals" text )

### Question ###
Name the round 16 for did not advance and light flyweight

### Accurate SQL ###

SELECT "Round of 16" FROM table_21687 WHERE "Quarterfinals" = 'Did not advance' AND "Event" = 'Light flyweight'