Unwanted blue cast with Fuji x-pro2

Does anyone have any bright ideas?
I'm shooting with a Fuji x-pro2 into a light box with led lights and a white background. The background comes out blue, although the colours of the flower seem near perfect.
I've tried working my way through all the white balance options including adjusting the K setting. Although this changes the cast of the background considerably it only seems to adjust it from blue through to red. I can't find a setting that gives me a clear white.
I've not had much success trying to correct this is Lightroom by reducing the blue hue.
Help!

Desaturate blue







--
Digital Camera and Adobe Photoshop user since 1999.
Adobe Lightroom is my adult coloring book.

The shot is most likely overexposed. Reduce the exposure and shoot again, then brighten shadows and midtones in post processing as desired.

From Raw Therapee, although from your posted JPG. You did work from the raw file, not the camera JPG, yes?

Is the same light source that is illuminating the flower also lighting the background?

What did you use for the white background?

Many things that appear to be white, such as printer paper, actually have a blue cast.

Yes, it's a Havox light box with Led lighting. No flash.

I used the white background supplied with the Havox light box I was using.