20 Unanswered Questions From 2017's Comic Book Movies
12. How Did Clark Explain His "Death"? - Justice League
The Question: With Clark Kent (Henry Cavill) being declared dead during Batman v Superman's final battle, how the hell is he going to explain to his Daily Planet co-workers that he's alive? They went to his funeral, mourned for him, and now he's back, at the same time as Superman no less.
The Likely Answer: Don't expect this to ever be addressed in any depth because it clearly doesn't make sense. Even if Clark went missing in the BvS battle, he wouldn't have been declared legally dead for seven years, so short of saying that a body was discovered in the wreckage that closely resembled Clark's, they've written themselves into quite the corner for the next movie featuring Superman.
Considering how the only semi-feasible explanations will be laughably convoluted, it's probably better for fans' collective sanity to just never ever address it.