Thank you for getting back to us, @usernabilissa.

QuickBooks Online (QBO) only allows you to convert an estimate to an invoice to deduct a partial amount from the original estimate. I understand that you're trying to change the decimal points when converting the estimate to invoice. However, QuickBooks is designed to display up to seven decimal places.

As a workaround shared by my colleague BettyJaneB above, you can consider creating an invoice manually instead of converting it from the estimate.

For now, you can visit our blog site so you'll be able to get the latest news about QuickBooks and what our Product Care Team is working on. 

Please post a reply below if you have other concerns with your transactions in QuickBooks Online. I'll be more than happy to assist you again. Have a great day and take care always.