InDesign will not keep image link

My InDesign will not keep links to some images.  I am using InDesign to create catalogues and often have 1,000 images.   I am using Winodws 10. 

All of the images are saved on a network drive with a mapped drive letter.  The location of the files are in a Amazon S3 Bucket.  A third party app called TNTDrive is used to map a drive directly to the cloud from my PC.  The locations of the images do not change and they are not edited in any way while my InDesign document is closed.   Modified date etc, remain unchanged,  But when I reopen, I find some or sometimes all of the images have lost their links and I have to relink them all again to the exact same path/location.