Camera mounts manufacturing error

I have just bought two Pi Camera mounts, they’ve arrived.
However one of them won’t go together, the second plate is too think, looks like a manufacturing fault.
Here’s a comparison, the top one is fine, the bottom one doesn’t fit:

It’s only about half a mil difference, but it refuses to slot in into the front plate.

Not a problem. Drop support an email and they’ll send you out another.

Due to the way Perspex sheets are made there’s a thickness tolerance which sometimes messes up the tight fit of the camera mount.