If you use the online service, any errors are highlighted as you complete the form This lets you correct them before sending it. If you submit the ESL with errors on it, you can log in and correct these up to 21 days from the date you originally sent it. After that, you won't be able to correct the errors online and HM Revenue and Customs may need to write to you to ask for the correct information.
If you submit your ESL by CSV or XML you can also use the online service to correct errors up to 21 days after you sent the original. Or you can submit a new file, Do this within 21 days, using the 'Correct declaration errors' page on the ECSL Online Service,
You can also correct mistakes, delete or add lines to an ESL submission, by downloading and submitting form VAT 101B EC Sales list (Correction sheet).