Hustle opt-in edit issue

For several times I tried to edit my Hustle opt-in.
I run a WP multi-site install, and I don't succeed in editing an existing hustle opt-in box. It just don't want to save the changes.
I click next, next, next and after hustle seems like saving, it just is right back to where it was.
The debug is on.
Please advice how to solve the issue