Please fill the required field error despite content input

All of a sudden I have a problem with the contact forms on 3 of my sites. They are not new sites. They were not recently updated. When i fill in the required fields i get the error ‘Please fill the required field’ in every case even though they are filled in correctly.

When i switch off the requirement on the fields i instead get the error ‘There was an error trying to send your message…’ for spam submission detected. When this happens ‘CF7 flamingo’ indicates the submission failed due to google recaptcha.

So when i disable recaptcha and fill in the form I get ‘message successfully sent’ and i receive the email… but the email (and flamingo) does NOT contain any of the info input in the form, its empty.

It seems the form does not recognise or pass on any of my input text or selections …and that is what is causing the errors and spam detection in the recaptcha.

I can confirm that the sites are successfully sending WP emails through SMTP and via other forms where input is recognised correctly.

The error remains even when ALL other plugs are deactivated and when the default theme is used. It appears to ONLY affect Contact Form 7. I can also confirm that the form is working correctly on a clone of one of the sites (on a different test domain).

I am completely baffled as to why these 3 sites have this error. They were built at different times and have different plugins. They are all hosted on IONOS but other sites on the same shared server have CF7 forms that work.

Can anyone suggest something i haven’t tried yet? I’m pulling my hair out!

Perhaps the plugin author has seen this before?

Many thanks!

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