can you upload the stl ?
And what slicer are you using ?

It could simply be either a flaw in the actul model or in the slicing.
Also have you either tried a new sd card or done a full format on the existing one ?

It's looking more and more like an issue with the model itself.

Which could be the actual original stl, the card or the slicer.

Also check all the wiring. It's unlikely a looses or broken wire would be that precise to produce that perfect section. But it never hurts to check.

But if you upload the stl I can have a look and run it through simplify3d and see if anything obvious happens.