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it might also take them a few attempts in updating your status, in my case the car would not appear until they had to 'force' it to do so. Upon each attempt I had to log out then back in again but wasn't a drama.
It took about 6 hours after I took delivery before the car appeared in my app. No "accepting" anywhere online or in app for me except for the lending agreement which was pre-delivery day. YMMV, as my state requires hardcopy paperwork signatures on the documents thus the "touchless" delivery is pretty much the same as before.