Why after typing an invoice for 3 hour and I send it and it says something is wrong and the invoice disappears?

Hi kevin134!

Thanks for reaching out to us. Let me help you in fixing the invoice issue.

It seems that what causing this is the accumulated temporary internet files in the browser. I suggest you check the invoice or create a new one using an incognito window. Here are some of the keyboard shortcuts:

• Google Chrome: Ctrl + Shift + N
• Safari 11 or newer: ⌘ + Shift + N
• Mozilla Firefox: Ctrl + Shift + P
• Microsoft Edge: Ctrl + Shift + P

Also, it'd be best to clear the cache to fix issues in QuickBooks Online and make sure to use a supported and updated browser. 

Need more references in handling accounts receivables in QuickBooks Online? Please visit this page: Sales and customers.

Leave a comment below if you need more help. Take care always!