Lucid will support secondhand vehicles, to suggest otherwise is nonsense. This situation seems very unique and all the expectation has been put on Lucid to figure out how to fix it with what seems like little effort \ research from the new owner. As in any situation, if you're not getting a timely response \ resolution over the phone then ask to be handed off to a supervisor (not Rawlinson who would have no idea how to resolve) or take the car to the Service Center and talk to someone in person.
"what service center" and "i haven't been assigned a service advisor"
A) how do they not know about service centers? every car company has them and can easily be found on the companies website but because he/she couldn't be bothered to do a basic internet search, here is the link.
https://www.lucidmotors.com/locations
B) You don't get assigned a service advisor until you're booked into said service center
I've been screwed over by dealers before and have had no issues showing up to the dealership, creating a scene and telling all people in the showroom to not buy cars from this company because the after sales support is non-existent. It's amazing how quickly a manager will come and usher you off the floor and get the issue resolved.