Placing damage on a benched pkmn REPLACED damage already there

Hello, so I am playing with Kyogre CRZ 36 and Inteleon and every time one placed damage on an already-damaged pokemon on the bench, it replaced the damage that was already there. I managed to capture a video because it happened twice previously, this recording is of the third time that game!

Exact sequence was:

Kyogre place 180 damage on benched Genesect.

Inteleon place 20 damage on Same Genesect -> total damage is now 20.

Kyogre place 180 damage on same benched Genesect -> total damage is now 180.

URL in case uploaded GIF does not work: https://imgur.com/a/ZBQUVYW