Thanks for your post in the Community, jennyw24!
Are you getting any error when lodging the IAS? You can lodge a nil report by finalising pay runs on the pay schedule with all the employees listed, but no earnings paid out. Then, lodge all those pay runs in that quarter to the ATO.
If you are lodging your PAYG Installment on a monthly basis, you can lodge 0 IAS. Make sure to enter 0 only without the $ sign.
Please reach out to the Support Team if you have any other questions at all or need clarification on the above scenarios.
Feel free to drop a comment below if you need more information. Have a great day!