Harvesting the wrong asteroid

[tomf]

This is in a modded version of KSP but I would be surprised if it was related to mods as none of them should affect resource harvesting.

For the casino contract for tourism plus I have a station  that has 4 asteroids attached. There is also a craft with mining capabilities that is also attached to one of the asteroids. When I try mining the amount of ore decreases in a different asteroid from the one the drills are mining, until the level of ore in that asteroid reaches 0. When it is 0 the drils tell me that resources are depleted, despite the fact that the asteroid that they are drilling is still full.

In the images you can see the miner attached to the asteroid on the left but the resources of the asteroid on the right changing.