Redirection not working

Hi,
The redirection suddenly stopped working on one of our sites. The form goes through, and we get the message on the bottom that it was sent, but it doesn’t redirect to the thank you page even though it’s set up correctly in the redirection settings.
The plugin is up-to-date, and we don’t have this issue on other sites with the exact same hostserver batch, theme, and plugins.
Thanks.

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