You must have done more than rename a partition… it is looking for the partition UID and not finding it. Since the UID is never supposed to change until the partition gets wiped, this is very odd indeed.
Also, putting external volumes (usb stick?) into fstab is not a good idea… let the automount find it when you put it in and want to access it.
Maybe if enough people file feedback on the name change they will reconsider. At least they will have a glut of feedback to deal with.