Alex
Trust me... my teacher account has far less than one million dollars, so the total funds in my account is not the problem.
Other teachers have had problems with italki's Withdrawal System in the past couple of months.
In fact, I did do what you suggested.
I tried to withdraw 100%, 50% and 25% of my funds, but just kept getting the same error message.
I hope this is not a problem for other teachers.