Problem importing photos into LR CC

As I have done previously when importing new photos into LR, I first created and named a Destination Folder during the import procedure within LR.   I then created a Subfolder (presumably within the Destination Folder) into which I wanted the group of photos imported.  My intention was to import the group of photos into a Subfolder within the Destination Folder.  The folders appeared to set up properly within the "Destination Section" of the import protocol, - with the Subfolder properly subsumed under the Destination Folder in the hierarchy - and with a "+" sign next to the Subfolder, as always; (indicating that the photos were to be added + to that particular subfolder).

However, after I imported the group of photos, the Destination Folder that I created was not listed (on left side of the LR window in Library mode, for instance) among all the other destination folders I have created in the past.  Instead, the Subfolder was listed without it being subsumed under the Destination Folder I had created.  The batch of photographs was imported to that Subfolder - but with no mention of the Destination Folder I had created.

I repeated the import procedure again a few times (with same batch of photos) and still did not find any listing of the new Destination Folder afterwards where it would normally appear in LR on the left side of the LR window.   I noticed, however, that on the first attempt at importing, the usual "+" sign appeared next to the Subfolder (under the Destination Folder) in the "Destination Section" of the import protocol.   On every subsequent attempt at importing the same batch of photos, the "+" sign no longer appeared next to the Subfolder, although the hierarchy was portrayed properly in the "Destination Section" before actually importing the photos.  I don't know if this anomaly is important in resolving the problem, but I mention it here anyway.

To summarize, the problem is that I would like the batch of photos imported into a subfolder under a destination folder.  The folder-subfolder hierarchy illustrated during the import procedure appears correctly  in the Destination Section.  After importing, however, the newly created destination folder is missing from the list of folders on the left side of the LR window (e.g., in Library mode).  Subfolder is listed there, however, and contains the newly imported photos.

Also, wonder why "+" sign is now missing from its usual appearance next to the subfolder during the import process.

Never had this problem before,  I suspect that I probably deviated unwittingly from the normal import procedure, but don't know where I could have gone wrong.

Any suggestions would be appreciated.

Bruce

P.S.  Am using a PC.