While loops forever

Im trying to have the program prompt the user for a valid input after inputting something other than a positive number, but this code just makes it loop forever. How would i get it to ask the user to input a valid input again?

cout << "\tAmount on deposit: ";
            cin >> deposit;
            if (!deposit || deposit < 0){

                while (!deposit || deposit < 0)
                {
                    cout << "\tPlease enter a positive number! " << endl;
                    cout << setw(60) << "Amount on deposit: ";
                    cin.ignore(deposit);
                }
            }else ...