It looks like you've made 2 transfer with this error. : ) No worries, Bittrex has your funds, they just don't know what to do with them as the memo doesn't match any SBD wallet account.
Just open a support ticket with Bittrex. They will sort it out for you.
https://bittrex.zendesk.com/hc/en-us/requests/new
RE: HELP! I Transferred SBD To A STEEM Memo...Where Is It?