Samsung S24 Ultra water damage repair advice

At the end of January 2025 my Samsung S24 Ultra stopped charging, so I took it to a Samsung service center. They found that the charging port had rusted and replaced it under warranty.

Two weeks later while on vacation I was taking pictures in the water when a wave covered my phone. It immediately stopped working, completely shut off, and I haven't been able to turn it back on since then (it's been two weeks so far). Since the S24 Ultra is supposed to be water-resistant, I suspect it wasn’t properly sealed after the repair in January, which likely let the water sip into the phone and cause internal damage.

My warranty expired in early February, so I’m unsure how to approach Samsung about this. However, since the issue seems to stem from their repair, I believe they should take responsibility. How should I present my case to Samsung next week when I'm back from vacation to ensure they repair my phone for free, given that they are partially responsible for the damage?