Comey was asked whether the DoJ ever tried to shut down an investigation and he denied it. The White House, and the President, aren't part of the DoJ.
Furthermore, the FBI is a branch of the DoJ. That there's some level of coordination between them is entirely normal.
What's not normal, at least in recent times, is for the President to talk to the FBI director. In fact, Obama reportedly told Comey at his swearing-in ceremony that that's the last time they'd ever talk to each other, at least as long as they both serve in their respective office.