What is JotForm?
JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
At JotForm, we want to make sure that you’re getting the online form builder help that you need. Our friendly customer support team is available 24/7.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
The checkbox to remove the JotForm Footer branding is grayed out because you're on the Free Plan. This feature/options is only available to paid plan users. Limits aside, this is technically the only other difference between a free VS a paid user.
To remove the branding, please consider upgrading your account.
Related guide: How-to-Upgrade-My-Account
I believe I have addressed your question already in https://www.jotform.com/answers/1077859
Kindly refrain from creating multiple threads about the same question/request in the future, to help us address them faster and in a much less error prone fashion. Thank you in advance.