Hello there, kryssage.
Thanks for joining us here in the Community. I'm here to get you pointed in the right direction for filing the IL-941 form.
If you received a tax notice about the IL-941 form from your state agency, I'd recommend you give us a call. Our Phone Support Team will be able to check your account and identify why the form wasn't received. One of them will request sensitive information about the account to check the status.
You can reach them through this article: Get help with QuickBooks Online
Please know that I'm just a post away if you need something else. You can reach out by posting a comment below.