Normally, I can access the Additional Attribute tab at ease to add more tokens to my current survey. But today, to be detail, 9/22/2017, I can no longer click on the Additional Attribute tab to manually add more tokens for my survey.

I do not know this is due to server's error or it was my survey's fault.

Please help me solve this problem.

Thank you in advance, and I am grateful for every kind help out there.