Does anyone know why my invoices in Bill.com are not syncing with Quickbooks? All of my income from January - Mid March is not showing up in my Cash flow sheet.

Thanks for posting in the Community, Meryl. Let me route you to the appropriate support regarding transactions that are not showing in QuickBooks Online (QBO). 

Transactions should directly go through your QuickBooks Online account when made through Bill.com. In your case, since several transactions aren't showing, I'd recommend contacting Bill.com. This way, you'll be advised if there's a need to set in the settings for all transactions to flow in QuickBooks Online accurately. And to check if they are having maintenance issues. 

In the meantime, we can temporarily record the invoices that aren't showing and mark them as paid. 

Here's how: 

Create Invoice 

1. Go to the + New, then select Invoice.
2. Select Add Customer and select a customer from the ▼ dropdown.
3. Fill out the necessary fields and choose Save and Close.

Receive Payment

1. Go to the Sales menu and select Customers.
2. Click the name of the customers you created the invoices with. 
3. Then, find the invoices you want to mark as paid and select the Receive payment button.
4. Input the correct amount received in the Amount received field. 
5. Once done, click Save and close. 

In addition, you may want to visit this article and learn how to personalize and add specific info to your sales forms: Customize invoices, estimates, and sales receipts in QuickBooks Online. 

If you have any additional queries regarding QuickBooks, kindly inform me by leaving a comment below. I'm always available to help. Have a good one.