I got my v2 on jan 6. I figured out the same thing, the middle of the bed is a little bit lower. I don't think a new bed would differ from this. I'm afraid this is normal.. I'm planning getting a BLTouch sensor, I think that is going to solve the problem

If you contact the seller and provide the picture of the bended bed, they probably give you a new one. But no guarantee that every piece of glass bed is perfectly flat.

The glass on my Ender3 V2 I received for Christmas was exactly the same!!  All the corners (the outside edges at least) were fine but the middle dipped.  And quite a bit too, as evidenced by the bed-leveling-with-a-sheet-of-paper test.  Scratchy on the outsides with a single sheet yet the middle felt like I could fit another 5 sheets in!

I ordered some new Creality glass bed sheets from Amazon and I'm pleased to say they were perfect so it's worth a try.  I've also read it's worth considering mirror tiles as a glass bed or even paying a visit to your local glaziers asking them to cut you some tempered glass panels to size.  Haven't tried this yet, it's on my list of things to do when Covid eases.

Incidentally, I'm finding my prints are better on the smooth (back) side of the Creality sheets rather than the treated dimpled side (which scratches all to easily anyway) so my thinking is that mirror tiles or glazier glass has got to be worth a consideration?

Mine was delivered 6th of Feb and mine is warped too

Hi, I'am using additionals clamps (foldback clamps) for the edges and some user put a piece of aluminum foil in the middle under the glass (40x40mm foil)...seams to be general topic