Is the iPhone 12 Mini water proof?

Hi all, Recently bought a new iPhone 12 Mini and after a month of use, the phone started to malfunction and stopped working completely. Took it to Apple for repair and apparently it suffered liquid damage with the LCI displaying in bright red meaning it was in contact with some type of liquid.

My first concern here is that the phone is indeed faulty as the phone was never in touch with any liquid so it's very hard to understand how this could have happened. Secondly, let's say for some reason the phone suffered from liquid damage, isn't it meant to be water proof up to 6m in water and not longer than 30 mins? Obviously Apple has the policy that due to liquid damage, the warranty becomes invalid and any repair costs is my sole responsibility.

Spent two weeks arguing with their team about this issue, as I believe such phones can be faulty and I do not expect a new phone to stop functioning completely after just 1 month. I am currently left without my new phone as I am not willing to pay for repair costs that are not my fault. Apple refuse to assist me here, insisting in obeying their policy which although I understand, makes client relationships very difficult.

Has anyone experienced the same issue or something similar? I have no other options on what to do, either pay the very expensive repair costs or purchase a new phone.

Any help or feedback is appreciated!!