Using 15.5.1 web client, there are some document classes where the realted documents topic is not showing up to enable the user to link documents. When I look at the relationships in the Layout editor the "document link" option is checked.
Hi Sue,
If the user is facing some issues on all the documents topic then check if the user has document link permission as shown in the below screenshot. If its only with some specific class then you can check in layout editor that specific class has a document relationship > click on edit and put a check on the documents relationship.
Let me know if you have any further quires.
Regards,
Deepti