This needs to be done by first writing off the bill via the Journal Posting:
In the Postings pick the tab Write-Off Journals.
Select the write off nominal needed and the matter the bill is on.
Put in the amount in for the write off and then OK/Next.
Select the Bill value you require to write off in the grid, if it is more than one make sure the values are on the correct bills in the list.
Select OK.
Once this bit is done you will need to manually adjust for the VAT from the write off nominal to the VAT nominal using the VAT journal:
Select the VAT tab.
Select VAT Journals.
You can create a Standard transaction template using the first posting you have.
Put all the details in from the nominal and Output VAT.
Once all this is completed to create a standard transaction select the button at the bottom Standard Transaction.
Create New.
Then put the required Code and Description in and click OK.
⚠️Important: If your company is Cash Accounting then the VAT journal won't need to be done as the VAT won't have been claimed for, you will need to take the value out of your VAT suspense nominal for the value of the bill and this can be done via the write off instead of using the VAT write off nominal you can directly go through the VAT suspense nominal.