Hi,
I am facing an issue while adding the marketing list from a sub grid in Campaign page. The + button is not functioning.When i click on the button, it does not responds. Below is the screenshot for better understanding.

I am the system admin and there is not security role customized for this. I can create marketing list if i navigate to marketing List entity. If i click on the next icon to + button where i can see the associated records and add list from there, still it did not get added.
I tried to publish the instance, application ribbon but still this button is not working.
I can suspect this issue only in UAT instance and in all other instances(dev, test and prod) it works absolutely fine. I even tried to import solution from other instance to UAT but still did not work.
Can anyone suggest me what else i could do to get this rectified?
Any help would be really appreciated