substance to sketchfab export problem

Hallo substance painter support community / team, i have an issue with the export from substance to sketchfab. The sketchfab option in the drop down menu of the the export textures field is grey and if i hover over it there is a message 'thís preset is not aviable for the current project'. I tried it on other projects and this problem stays the same. Reinstalling substance painter doesn't fix this problem. I hope you can help me to fix it.

Greetings V.