I'm building Ares' fortress and stuck at 90%. It says it will require additional 4 slabs of marbles and 2 sculptures. I have lots of them on my stocks, but they don't finish the production. I tried everything, put stockmarkets nearby but nothing works. I need your help!

Off the top of my head:
1) Make sure you didn't halt construction by mistake
2) Make sure you are not stockpilling the materials
3) Make sure you have Artisans' Guild and it has workers
4) Make sure there is road between Sanctuary and the needed materials.
If all of above is not fixing your problem try to make sure that stockyard that has the materials has them on accept not get.

May help to relocate some of the materials closer to the sanctuary may read as no material available if to far away

No, they will go to the other edge of the screen for building materials (however, it WILL take a long time than - isn't that your problem? How long how you been waiting? It might be that the needed materials are being transported to the site).
Anyway, it's a good idea to have a warehouse set to get Marble, Wood and Sculptures in the vicinity of the planned Sanctuary so that the transport carts don't have to travel far for the materials.

make sure your not exporting the materials cuz i seem to remember reading somewhere that exports take top priorty over any of your building projects and of course make sure your not stockpiling it at a warehouse.

If you look at the last page of the menu (I think?) where it talks about what your have in inventory it usually tells you what the problem is caused by don't have the game installed atm to check but it is listed in one of the monthly report tabs.

Beakie