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I removed the lens to show to the shutter release. While putting the lens back on I didn't place it correctly on the first attempt. Also, when I removed the lens, the camera was on and possibly in live view.
Now, the aperture doesn't change while in Live View mode. (Yes, I'm holding down the -/+ button. Also while it is on manual.) I can only change the aperture while in viewfinder mode.
Did I mess something up? Or is it in the settings somewhere?