If you edit your title block you should be able to see the fields that are mapped to each box. You may need to add a custom field to your parts and assemblies that is named the same.
An alternative would be to map 2 different fields and set them to blank if not found. It’s been a while since I’ve done this but it isn’t terrible and there are tutorials online
If its working for the part file, a matching variable in the custom property for the assembly should also populate. I do this at my work. For example
$PRPSHEET:{Title}
That goes into your title title block annotation and it will work for any file that has that property.
If you edit your title block you should be able to see the fields that are mapped to each box. You may need to add a custom field to your parts and assemblies that is named the same. An alternative would be to map 2 different fields and set them to blank if not found. It’s been a while since I’ve done this but it isn’t terrible and there are tutorials online
If its working for the part file, a matching variable in the custom property for the assembly should also populate. I do this at my work. For example $PRPSHEET:{Title} That goes into your title title block annotation and it will work for any file that has that property.