if you still have trouble after that then go back in to safe mode and run the Factory reset on the top menu, not the wipe device option (be patient it can take up to 10 mins for this to happen), it may carry on pinging forever then all of a sudden reboot, so don't think that nothing is happening and reboot manually
then see if you can get into it after that,
if not then you need to ring SonicWall support and go through the firmware recovery procedure
Answers
@Theef is it a brand new device? does it go in to safe mode? upload the latest firmware and then boot with factory defaults,
https://www.sonicwall.com/support/knowledge-base/how-can-i-put-the-sonicwall-into-safe-mode/170507123738054/
if you still have trouble after that then go back in to safe mode and run the Factory reset on the top menu, not the wipe device option (be patient it can take up to 10 mins for this to happen), it may carry on pinging forever then all of a sudden reboot, so don't think that nothing is happening and reboot manually
then see if you can get into it after that,
if not then you need to ring SonicWall support and go through the firmware recovery procedure