Please note that the Bittrex API is currently only delivering the transactions for the last 30 days and only the last 100 deposits and withdrawals. 

Bittrex is already working on a solution. 

To import all trades, we recommend to use the Bittrex CSV import first and then activate the API. 

Thus, all past and future trades will be imported.

Please try it like this:

- Delete all Bittrex entries with "Bulk Edit/Delete" button on the Enter Coins page.

- Upload the CSV file with the Bittrex CSV import first.

- Let the API import job run.

- Check if your balances match your current holdings.

Do it in the exact same order and see if it solves the problem.

If some of your deposits and withdrawals are missing you will have to add them manually.