This is what I see (with 12.17.6) with that config when opening the formats list. There's a similar but slightly different wildcard format there initially:
After clicking OK and re-opening Preferences, it is still there, although the backslash on the end has been removed (which is normal/fine, but we'll make it so that happens immediately instead of after reloading):
I re-entered F:\Video Series\*\ and it seemed to work. I don't know what happened to the original format I made but this new one seems to be applying over it (or perhaps it's overwritten it?)