The entire ocean floor is mapped. This can only be gross incompetence piloting the sub or as other players have suggested, china created a new mound on the ocean floor there.
Oh really? As of Jun 2020 it was 20%.
https://www.theverge.com/21299017/earth-seafloor-map-how-much-mapped-ocean-seabed-2030
“The entire ocean floor is mapped. This can only be gross incompetence piloting the sub or as other players have suggested, china created a new mound on the ocean floor there.”
Now that I give this some thought, it IS possible that the floor of the ocean could change, especially around the “ring of fire”. Nature may have created a new mound. Underground volcanoes have to start somewhere.