How can I allocate payments received (and entered into the bank) to the invoice produced after?

We can link the payment to the invoice, stephen-toplis.

Once the payments are available in the Banking page, you can match them to the Invoice you created. QuickBooks suggests possible matches and you'll just have to review the transaction to link it to the correct invoice. 

Let me show you how: 

1. Go to Banking from the left menu. 
2. Click the blue bank tile. 
3. Look and click the payment in the For Review tab. 
4. If you see that it has multiple record found, click the Invoice link to review. 
5. Select the Find match option if there are no records found.
6. In the Match transactions window, filter the dates to when you recorded the Invoice. 
7. Check the invoice and then click Save. 

Matched transaction are now transferred to the Reviewed tab. Aside from matching transactions, there are also ways on how to handle downloaded bank transaction such as categorising, assigning or adding them. 

Reach out to me if you have further questions in recording received payments from your customers.