I have a newer 2020 domestic A/C, which runs fine. However, the last couple times camping trips, it seems to not start up correctly once in a while. Usually, it runs fine cycling on and off as normal....
Let's start with where you are at when this happened. Campground? It could be you are not getting the required voltage. The campground has to feed the whole place. In the late afternoon, there might be less of a draw from other campers.