Unfortunately Bungie does not restore deleted or lost items or characters. the only way that a character can be deleted is manually with your log in info. So, if you did not do it, you might want to change your passwords.
[quote][url=https://www.bungie.net/en/Help/Article/12211]Whether due to accidental deletion or unauthorized account access, Bungie does not recover manually deleted characters or items, and does not replace in-game items that are lost or dismantled.[/url][/quote]