"Kyiv (/kiːv/ KEEV)[10][citation needed] or Kiev (/ˈkiːɛv/ KEE-ev;[11][12] Ukrainian: Київ, romanized: Kyïv, pronounced [ˈkɪjiu̯] ( listen)) is the capital and most populous city of Ukraine..."

https://en.m.wikipedia.org/wiki/Kyiv

Both are correct and with 30% of Ukrainians speaking Russian they would pronounce it as Kiev.

This is like nit picking French Swiss saying Genève while German Swiss say Genf. Both are correct.