Empty a brush without confusing capsule size

Try direct brush delivery

1. Keep the collected dust in the brush.
2. Return to the station's collection slot or return opening.
3. Use its deposit interaction with the loaded brush.
4. Check that the carried amount is transferred; do not infer loss from the appearance of a single capsule.

Compare amounts, not one container

A capacity upgrade can let the tool hold more dust before it fills. That does not mean each capsule becomes larger. When testing packing, compare the tool's starting amount with all capsules produced and the amount remaining in the tool.

The original poster described a 2 kg state producing only 1 kg, then reported normal behavior in a new game. That follow-up does not establish whether the cause was a patch, the save or something else.

If you can reproduce missing dust

• Record the exact brush, its capacity upgrade and the starting dust amount.
• Count all generated capsules and check the remaining tool amount.
• Record the installed version and whether this is solo or co-op.
• Keep the existing save; starting over is not a demonstrated repair procedure.