Problems with .obj exporting

Hello there, guys. There is a problem here.
I’m making furniture models, that i need to export to .obj. In Blender viewport everything ok, but in site, where final model must be, half of my work is… Idunno… Broken maybe.
There are Photos of my problem (right side - Blender, left side - site viewport)
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Maybe, I made some mistakes with exporting settings?!

Dont know Site. but maybe you could try this to see if it fix the export:

Mmm check if you:

1.- Have apply all transformations before making the export. (ctrl + A) select All transformations
2.- Apply all modifiers. (The wrench icon)
3.- Select everything, enter edit mode, faces mode and click alt-N (Normals menu) and select recalculate outside. Or shift-N.

Then try to make the export again.
If the behaviors persist, please take a screenshot of the obj options that you are selecting to give a better idea.

Good Luck