Hawthorne kept my $1,400 deposit and sent a collections notice for $780 more

Moved out after 14 months at a Hawthorne property in University City. Left it cleaner than I found it. Move-out report arrived 31 days later, NC requires it within 30. Even though the report came late, they still kept the full deposit and sent me a $780 collection notice for 'resurfacing' and 'deep cleaning.' I'm disputing both the timeline and the charges.