I transfered ada from bitmart to binance US twice today. This was hours ago and I they still have not been deposited.
Perhaps the transactions are delayed… it happens often on exchanges… I waited 4 days last time 
If the transactions were with success then u should have patience
Go to bitmart and lookup the status of the withdrawl. What does this say? And also is there an ADA address that is already on the blockchain. If it is not, then the delay is at the side of bitmart. If the transaction is on the blockchain than the delay is on the side of binance (assuming you have used the right binance address).
It shows complete on bitmart side. I have transferred to this address before. So it must be on the binance side. It’s been 12 hours now.
Generally speaking never use the same address twice.
Why not? 
If it shows completed on the sending side then there should also be a transaction id on the blockchain. Go to binance and show this tx id and ask them what is wrong.
That is not always possible with exchange addresses since they decide for you which address to send to.
When using your own wallet you can indeed generate a new address to stay somewhat more anonymous. Although that is a hard thing to really achieve.