Manage Value set - not able to enter any values
I have created descriptive flex field for create payment UI.
in that Descriptive flex field, I cannot able enter any values in the value set -
->Manage Value Set
Query the Values set name.
Edit the value set that I created. Edit value set opened but manage value button is grayed out.
Please help me, how I can enter values of the Descriptive values set.
Please find in the attachment.