Most sites automatically assign addresses to users that has a time limit. It doesn't necessary mean that the funds cannot be retrieved after that time period. In many instances, they do not actually delete the private keys and it is still possible to be retrieved.
Since you do not have any confirmations, there is still a slight chance that the transaction can be dropped by the mempools around the network. Is your wallet pruned? If not, try running it with zapwallettxes. I'm too lazy to explain how so refer to this:
https://bitcointalk.org/index.php?topic=1289559.msg13273042#msg13273042.