The VAT quarter needs to be closed before the next one can be opened up, follow the below to close the VAT quarter:
From the Main Menu go into VAT Management.
Highlight the VAT quarter you want to close check this has a submitted date in.
Select CLOSE if the VAT REPORTS have been run.
If not then select the VAT REPORTS button, select RUN BATCH.
After all the reports are run select CLOSE.
If you need to Delete a wrongly opened VAT quarter you can just select the CANCEL option instead of CLOSE, this will delete the VAT Quarter that you have opened.