Saving Files

In my workflow, I export files from Lightroom as a TIF file and make any additional changes I need (usually very few) When I try to save the image, I get a message in Photoshop saying that the file cannot be found. The same happens if I try and save as a JPEG, which is the normal last step in my workflow. I can see the TIF file in the correct folder in File Explorer. This has only started happening in the last few days. I am using a Desktop connected to One Drive which is fully up to date. Any ideas why it is going wrong?

Following on from above, I subsequently uninstalled Photoshop and reinstalled latest version (previous version had been loaded about 3 weeks ago.) After re-installation, problem seemd to have been cured but after 3-4 save activities cam back. Still have no idea where to go next.