They blew one up in 2015 as well. There have been other issues that haven't been as catastrophic, but problematic.
NASA hasn't stated that they are signed off on the explanation and fixes yet so it remains to be seen when Space X will be able to resume shipments to the ISS. SX also planned to fuel manned rockets with the crew onboard instead of the tried and tested procedure of installing the astronauts after the fueling is complete. Something else that NASA isn't going along with.