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Replacement parts for WHIRLPOOL ED27RQXXW00 REFRIGERATOR | AppliancePartsPros.com

It looks like the liner is obsolete.

Try loosening the mounting screws to see if that helps.
If it does, do not over tighten the screws when re-tightening them.
You may have to slot some of the screw/liner holes so you can hold it un-warped.

You could try removing it to see if it will return to it's original shape.
Most plastics have a memory and will return to their original shape if warmed up a little.
Putting it out in the sun for a couple hours may help.
Of you could try warming it up with a hair dryer.
Do not overdo it as you can actually make the warp worse.

If all else fails you could try a jiggery pokery.
Note: I have never done this so cannot say if it will work but it may be worth a shot.

Remove the liner and see if it will return to it's original shape or at least close to it.
Then get a piece of styrofoam that will fil into the door depth.
I would use the blue or pink type (closed cell) and then glue the liner to this to strengthen it.
Be sure to use a glue that is compatible with styrofoam. Many glues will eat it.
Put some weights on it to hold it flat on the styrofoam till it dries.
Of coarse do a dry run before buying anything to check that flattening if actually solves your problem.

Another possibility is to use bolts/screws to hold the shelving bins in.
I am not sure if this is possible with this lined.

With luck someone else will jump in who has actually fixed a warped liner!!!