A file ending 0045 already exists.
As this guy would say "What he said."
@Welshy74 I have to agree with ecoleman.
It is likely that maybe you already have an existing filename when you attempt to rename other files, thus Lightroom will add
-2 at the end. When using a numbering system, and when renaming again for the second time after you already renamed them in the first place, it can cause the software to get confused, and also the human could missed something there.
Wouldn't it be more effect if you tick what you want to import and uncheck what you don't want to be imported, then import using the renaming system, in the first place? Or you could import, edit/delete, rename once, instead of import, rename, edit/delete, then rename again.
My photographs use numbering as filenames, so I always import what I really want to keep, uncheck any photos I don't want to keep, before I import and let LR rename them. So far I never had any problems with filenames.