How can I delete emails in my mailbox that are not responding to the "delete" commands?

Look in the Saved Folder. Messages > Saved Messages.

I checked the folders and they are empty.

Are you on a BES system?

I'm not sure.....new phone and up until today Ihad no issues with keeping the inbox cleaned up. Now I can delete new incoming messages but there are a few that continue to exist (incoming and sent) that regardless of how I try to delete them, won't delete.