Generally, the funds are withdrawn on the payment date you specified if your return has been accepted and is being processed. Sometimes, it may take a couple more days on their end. If you still don't see the debit 7-10 days after your return has been accepted and it's already being processed, you can contact your state tax agency. If you didn't specify a date for the auto-debit, April 17th is the default payment date.
You can go here How do I contact my state Department of Revenue? and choose your state and it will take you to their contact page with phone numbers to reach them.