Imac late 2012 display corner marks

Hello there,

I discovered two tiny (but still visible) marks stains?! on the lower left, and right corner of me display visible when it's blank, white. I have this machine for one year on the dot spent nearly 3 grand on it a bit of a frustrating one.

Any of you guys know what causes those marks or any of you facing the same problem ?

 

And picture of the left this is a tinier one

 

You won't believe it guys

This is me dehumidifier working in the room. They had exact the same stains on the machine I never care about that just wiped them off the machine. it's kind of a mouldy stain. I realised after I looked behind the machine found some marks on the back as well.

It made me furious now.

This is ridiculous I already messaged the company.

I don't really know what to expect I'm speechless now