Cannot Import Nikon Z5 + FTZ with Sigma lens to Lightroom mobile

Hi,

I've a new camera the Nikon Z5. 

When i'm using the kitlens i can import images to lightroom. 

When i use the FTZ adapter for older lenses, in this case the Sigma 17-70mm F/2.8-4.0 DC Macro Contemporary OS HSM Nikon i'm unable to import these to Lightroom Mobile. 

This was also the case with the Lightroom Classic edition i believe:

https://feedback.photoshop.com/conversations/lightroom-classic/lightroom-classic-lens-support-nikkor-16mm-f28d-with-nikon-z5-and-ftz/5f5f462a4b561a3d4277848e?page=1