Hi my invoice calculate vat wrong , i have now invoice with total amount 22,500 with vat 5% it must be 1,125 but give us 1,071.42.

Let's try to check the VAT rate that you've set, @salah_eltayeb. 

Follow the steps below on how to check it:

1. Go to Taxes from the left tab.
2. Click the Edit VAT drop-down and select Edit rates.
3. Select the VAT rate that you've used for the invoice that has a wrong calculation.
4. Click the Edit button to view and update the rate.

Here's more information on how to apply Sales Tax to Transactions and Sales Forms. 

Stay in touch with me if you got more questions about VAT and or anything else. I'm always here to assist.