How do we disable the "build a jotform for free" when the thank you is delivered to the person surveyed?

If the form is under a paid account, you can do that through Settings page https://www.jotform.com/myaccount/settings and just uncheck JotForm branding:

Let us know if you have any further questions.

Thank you!

It was not checked, but still asks “create a Jotform” Free…. how do I stop that. We are a silver customer and that is a problem for our committee
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I cleared your forms cache, please check, the footer should be removed now. (I did a test submission, please ignore)

If you experience any further issues, please let us know.

Thank you!