So i'm playing FTB Academy 1.4.0 with my friends on a server, 1.12. Actually additions version 1.12.2-r151-2.
I have tried using the auto placer to place blocks and it doesn't work and i'm unable to find out why. Looking up the problem isn't helping me so wondered if anyone here knew?

On a related note: i tried using the block placer from industrial foregoing instead and it has the same problem, wont place blocks.

I assume you're using some sort of chunk claiming mod to stop other players from building in your area. Depending on the mod you use, you'll have to disable the claim or allow fake players to edit blocks in the area.