Navient doesn’t send a bill

Navient doesn’t send a bill out in the mail. I’m always getting a letter from them saying I’m late without getting the actual bill before the due date. Now I’m responsible of sending my bill out on time but I can’t do that until I get that letter. Now I think they tapped into my debit card and took $200.00 without me authorizing it. My checking account is missing $200.00 from pay my bill & I’m assuming its from sallie Mae. Please help me out who took my $200.00 from my account.