Email - how to delete mass amounts - Time Warner Internet

This question is about "Email - how to delete mass amounts", with Time Warner Cable internet and apps. Someone posted a solution and it was marked as solved but it must have been for deleting in outlook. I need to delete many from my wife's account via webmail and i have it set to display 100 per page (max that I see) but when I click the select box at the top to mark that entire page and then hit delete it works for a minute but the emails are not moving. Since it moves them to the Deleted box I wonder if it's not working since she's over quota. On the phone now on a 35min wait to see if anyone at Spectrum can assist. I guess since it's POP email, a created an outlook acct. hoping to do it in a real interface but the emails aren't showing up.... I assume since it's not an exchange acct.

Email - how to delete mass amounts?