My question was put on-hold recently with a banner:
put on hold as off-topic by R S, Melebius, Pilot6, user68186, vidarlo - 9 mins ago
But R S is me and I don't remember I did that to myself.
It seems it's more about hardware/software not related to Ubuntu.
Probably you wanted to just add the comment and accidentally picked the close option instead?
Anyway, it is reopened now.
When you earn 250+ reputation points, you also earn "view and cast close and reopen votes on your own questions" privilege. Some time in the past you might have cast a close vote on your own question (may be unknowingly). That's why your display name is being displayed on the banner. You can confirm the close votes you have cast in closure tab under votes.
Update: The question has now reopened. You are one the user who voted to reopen the question just like you were one of the close voters. For more information, see timeline.