This isn't the kind of service we want to leave you with, @contact59.

As much as I would love to assist you, bounced email when sending invoices or reminders to customers is already reported and our Developers. They are diligently working on getting this issue resolved. Thus, we're unable to provide a timeline when this case will be fixed.

If you've already contacted our Customer Care Support, you're added to the list of the affected users. By then, you'll receive updates of the issue through your email. You can also contact them to check the status, just provide this case number INV-70915.

In the meantime, you can continue to follow the workaround when sending customer invoices.

I'll add this link in case you need help with other customer-related tasks. It contains customer topics with articles and some videos to guide you. Pick a title that'll fit your concern: Sales and customers.

Please don't hesitate to reply to this thread if you need help with anything else or if you have follow-up questions. I'll be around for you. Take care and have a good one.