Unable to update a D- list

[samson]

I have a cube with 2 tabs and 2 context filters. In the cognos contributor for web few of the users are able to filter the data based on the context filter where as few users aren't able to filter it. All the users have same level of access. I uninstalled the web client and reinstalled it but still they have that issue. The context filters shows up but when they click on it nothing happens. Any insights in to this issue will be helpful