In order of my google search's results.
https://thehill.com/policy/defense/4043221-ukraine-kakhovka-dam-collapse-theories/
https://www.nytimes.com/interactive/2023/06/16/world/europe/ukraine-kakhovka-dam-collapse.html
https://www.bbc.com/news/world-europe-65818705
Most of these articles admit that it is kind of impossible to know for sure in the middle of a warzone. It's as likely that it collapsed due to lack of proper maintenance in the middle of a war.
What's your source?