BSP wont delete

ok, just ran into a weird issue and am hoping someone knows how to fix it… tinkering about with creating a cave, and dropped in a BSP. was trying to make it physical, so i told it to make a static mesh, and hit thing that said what type of object i wanted, so i set it to be solid… because on my test runs i kept falling through it. still didnt become solid, but i decided to delete it and try again a little later. but somehow theres a duplicate sitting there now, that i can pull up details on, i can select it to copy/paste, but i cannot delete and it doesnt show up in the actors tab anymore. it also only shows up on the Lit view mode. any idea how i can get rid of this thing?

after much trial and error and frustration -

if you have a BSP that wont go away and isnt being listed in the scene outline, go to build, and rebuild all the geometry on the level to see if that gets rid of it.