Writing Keywords Error

I'm still getting an error when writing keywords to metadata, here is my workflow and software versions:

Bridge - 9.1.0.338

ACR - 11.4.1

Photoshop 20.0.6

I upload my RAW CR2 files to a Synology NAS via the Bridge 'Get Photos' import tool, I select 'Preserve Current Filename in XMP' and apply a metadata template with copyright data. There are no errors at this point.

Once uploaded I navigate to the CR2 files on my Synology NAS using Bridge and open the files which open into ACR. I apply lens corrections and remove chromatic Aberration and then click open and go to Photoshop.

I carry out my editing as required and save the edited file as a TIFF with layers intact to a new location on the NAS. I then flatten the layers and save the file as a JPEG to the same location. I then navigate to the CR2 file and move it to where the other two files are located. I then select all three files and stack them together.

The next step is to apply keywords and with all three files highlighted I select the appropriate keywords. The CR2 and JPEG keywords apply correctly but the TIFF file generates an error 'There was an error writing metadata to _MG_8066.tif' and I get a horizontal line on the keyword box instead of a tick. If I then close the error message and then click the keyword again it writes correctly to the tif file.

The same happens when removing keywords as well. I don't see how the network drive is the issue because it works with the other files and then works on the second selection?

I cannot see why this happens but it is irritating, this has to be a bug within Bridge as it never happened in the past and only really started to happen about 3 or 4 versions ago. It is possibly to do with the tif format or the tif file size which can be quite large but why would it then apply the keywords on the second attempt? I don't have any other issues with using a networked storage location.

I have been putting up with it but it is getting tiresome now so does anyone have any suggestions please?

Thanks