Keep getting an error message while trying to send invoices, I cant save or send some invoices, others have sent.

Thanks for notifying us of your concern, @Midwestmgs. 

As per checking, I've confirmed an ongoing investigation into being unable to save invoices in QuickBooks Online (QBO). Rest assured that our engineers are diligently working to resolve the issue as soon as possible so you can get back to business.

In the meantime, I recommend reaching out to our customer support team. This way, you'll be added to the list of impacted users and receive email updates about the investigation. To do that:

1. Go to the Help icon and choose the Search tab.
2. Select Contact Us.
3. Describe your concern and select Continue.
4. Choose between Chat with us and Have us call you.

When your customer makes an invoice payment, record it in QBO fully or partially to ensure your books are accurate and up-to-date.

Let me know in the comments if you need additional guidance about saving and sending invoices. Our team is always available to assist you further. Be safe, and have a good one.

I've already spoken with them, and have been added to the list.  We thought we had a work around, (go to the customer and create an invoice from there, I was able to save it and send the invoice!!) and it worked for the first invoice, but not any others.  This makes no sense to me!  Yesterday some would send and not others.  You need to get this fixed as we have to be able to send invoices!!  I will go back to desktop if this keeps on much longer!

I uploaded the QB app, and you can start an invoice on there, and either send from there or just save it and go to online and finish it....This worked for me yesterday for multiple invoices, have no idea if it will work all the time or not.