I know some information regarding this, clarkerdny.
When Sales Receipts do not appear on VAT return, it can be due to the incorrect VAT rates assigned to the sales receipts. With this, it's best to check if the attached VAT rate to your sales receipt is correct.
Kindly follow these steps:
Go to the Sales menu on the left navigational panel and choose All Sales.
Find the sales receipt in question and click on it to open it.
Check the VAT rate assigned to the sales receipt in the VAT field.
If the VAT rate is incorrect, click on the Edit button and select the correct VAT rate from the drop-down menu.