First, search through the vault and the inventories of all your characters. If it isn't there, try turning your console off and on (obviously). If that fails, try clearing your console's cache. You'll have to Google how to do this, as I'm no expert on consoles. If that fails too, try power cycling your networking devices (router, modem, etc). There's unfortunately not much else that can be done. According to Bungie's Deleted Item and Character Policy (https://www.bungie.net/Mobi/en/About/Article?id=12211), Bungie does not restore deleted/lost items or characters for any reason. I'm sorry your items were lost and I hope you find them with the tips I've suggested. Good luck!