Armature error: multiple data blocks

Good day all,
i have the following issue:
image

The problem is:

  1. I don’t know how this happened
  2. This is somehow causing errors with bone constraints

So I would like to “merge” these two data blocks back into “Armature”, but for example copying and pasting the bones doesn’t seem to work (it just creates a new datablock instead of replacing the bones in “Armature”)
I’m using Blender 4.02

Any help appreciated.

Thank you

you can use CTRL+J to join (merge) armatures

Yes thanks for that info, but these are in a single armature object. So I have the “Armature” object which has these two data blocks. It makes no sense at all!
It might be that I don’t know what I’m looking at but it looks like a bug of some sort, since I didn’t do this intentionally, and I wouldn’t know how to be honest.
Additionally there’s no way to copy the bones from one data block to the other, so it can’t be fixed that way apparently, and that’s why I’d like to be able to merge the two data blocks.
image

Oh I think you are misreading the UI.
It’s not that the armature has those two datablocks, you can choose ONE of those datablocks FOR your armature.

In fact the latter is now no longer used and will disappear when you reopen the file (indicated by the 0 next to its name)

Following on from @_hris, that selection box is for choosing which data block the armature is using.

If you want to Ctrl-J them together you need a second Armature object to join with the first one.

Create a new Armature, then in it’s data block, you can select the Armature.002 data.
In your first Armature select the Armature data block. You can ignore the new armature data block that will have been created by the new Armature.

Thank you both. Following the advice I was able to “move” the actual bones to “right” armature, and to dissolve the unused armature datablocks.