Contact Form broken after 5.1.1 üpdate

After the latest Contact Form 7 update and integration of the new reCAPTCHA version I receive a lot of spam on one hand and on the other it seems like I am not able to receive any messages anymore. When I test the form, I end up with the orange warning. I already looked into the documentation about this, but it did not help. The only way to stop this is to remove the reCAPTCHA integration and use the security question which does not work so I end up with tons of spam again.

Thanks for your help in advance!

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