I just moved it. Click the pencil to edit the title and it will give you the option of changing the category.
As I said, I’m a bit challenged since I’m new to this forum. When I’m in edit mode there is a red slashed circle when I hover over the title and there only about 6 extremely broad categories available. I chagned what I could.
Replying in reverse order here:
@fedoradan No problem. There are only supposed to be the few broad categories — we didn’t want to over-complicate things for people. But I think the addition of the Common Issues section adds a wrinkle… you’re not the first person to be confused.
I’ve added a site change  which makes “Ask in English” the default category — I think that’ll make things less confusing. And we can always move misfiled things. You couldn’t edit your own post simply because you’re at a relatively new-site-user trust level. It’s okay to flag for moderator help in this case.
@kparal You should be able to do what Ben did (the pencil by the title) for all posts in the Common Issues area, because all members of the bug triage group should also be moderators in that category. Let me know if that doesn’t work for some reason. I’m also happy to also add you as a general moderator if you’re willing.
Sorry for the delay @mattdm, some month ago when we started the discussion I’ve instaled a dev. env. of discourse inside a container, I’ve instaled all the three plug-in available for multilingual site, and if I remember well, you need to TICK on Discourse automatic detection $USER browser Language configuration setting.