"To confirm the deletion" means to agree or approve the action of permanently removing or erasing something. It suggests that a person needs to give their consent or affirmation before a deletion can be carried out. Full definition
It also provided a signed statement confirming deletion of all the improperly harvested data. (ecommercetimes.com)
According to the article, Scribd confirmed the deletion in a statement, noting that few users had taken advantage of the comics content. (ebookevangelist.com)