LR Mobile consuming 13.6 GB in Local Storage with 0 photos

I use LR Mobile (LRM) on my iPad when I am on the road and away from my desktop where I run LR Classic (LRC).

On my most recent trip I loaded around 2500 images, mostly RAW files and did various edits as I went along. They slowly synced to the cloud.  

When I got home I pulled these images and the associated edits down and loaded them into LRC.  I then deleted all the images in the cloud using LR through a browser, including removing them from the "Deleted. Folder"  I also did the same thing on my iPad using LRM – including deleting from"Deleted. Folder" there too.  To be clear there are 0 photos in All Photos and 0 photos in Deleted.  

My iPadStorage report shows that LRM is consuming 15.2 GB, 300 MB of app and 14.9 of data.  
LRM's Local Storage report and it says it is consuming 13.6GB.

LRM's Cloud storage report says that I have 99.9% of my cloud storage free with a few MB in use.

How can I free up that 13.6GB of consumed null storage so it is available to other apps on my iPad?

Many thanks for any suggestions.