Hi info-alkoelectri,
Welcome to Community! I can understand the concern, when an 'undelivered' error appears, when sending invoices to your customers, in QuickBooks Online. The error you've received has been reported by other customers, and this has been escalated for further investigation with our Development Team. Although I don't have an ETA for resolution, you can contact our Customer Care team at 1-855-253-1536 from Monday to Friday between the hours of 9 AM and 8 PM EST. They will be able to add you to the list of affected users, and set you up to receive an email notification when it's been fixed. In addition, they'll be able to look into your auto-payroll concerns as well.
Please feel free to reach back out with any other questions. We would be happy to help!
