I put my phone on airplane mode. I used to try to study for hours straight but toward the end I was burning out and just set a timer on my phone for 90 min and I would take a quick break and then reset the timer.
Think of it as 4 or 5 individual sections instead of a four hour ordeal. Reset after each section.
I second what the 7sagers above said. It will get easier the more you do them.
I think you should just call them and ask- they'll most likely cancel it and have you do it again (they'll reset it for you). I don't think it will pass the security check like that.
The last RC was extra abstract and esoteric IMO. Just attempted to take the online writing section and the software crashed, meaning I have to petition for LSAC to reset the launch link for me and discard my first attempt. Great, lol.
Maybe step back from studying for a few days, give yourself time to reset. Racing against the clock doesn't help much with the LSAT, but your mental state can make an enormous difference.