John-Joe O'Toole scored Northampton's equaliser on 35 minutes after hosts AFC Wimbledon took the lead on 24 minutes through Azeez.
The Dons had the majority of chances during the game but failed to break down a resolute Cobblers side for a second time.
Chris Wilder's men lie 10th in League Two with 15 points from their 10 games to date.