Problem about delete invoices

Dear communities:

I find difficulties in delete my data
I want to delete lots of my customer data
it shows that some of them are related to invoice so I cant delete them
then I use data import tool to change the invoice status as "cancelled’ in order to delete them
but its shows that I cant change them after submission
It means that I have to cancelled them term by term?

thanks

@1117
Please refer the link below to learn more on how to delete submitted documents.
https://frappe.github.io/erpnext/user/manual/en/using-erpnext/articles/delete-submitted-document

Hope this helps.

@ArundhatiS
I know these steps
My problem is :
I can only change one status of my invoice ?

I would like to know is there a more convenient solution?
thanks