Forget the constitution or martial law, its a democratic state and its own people have said they do not want elections while a war is going on, that also goes for the opposing political parties.
Two of Zelenskyy’s main political rivals, Petro Poroshenko and Yulia Tymoshenko, have publicly rejected the idea of wartime elections as impractical and illegitimate. Ukraine’s vibrant civil society has also voiced its opposition to the return of elections before a peace agreement has been signed. Meanwhile, a new opinion poll conducted in February 2025 found that 63 percent of Ukrainians are against holding any national votes until the war with Russia is over.
https://www.atlanticcouncil.org/blogs/ukrainealert/ukrainians-are-proudly-democratic-but-resoundingly-reject-wartime-elections/