Emails dont send CF7

Hello

For more than 7 days our contact forms don’t send any emails. We are getting always this message: “There was an error trying to send your message. Please try again later.” and also this “*** forbidden. you sent forms too often. please wait a few minutes. *** “.
We set up the SMTP and verify the server but is everything ok.
When the clean talk plugin is deactivated the emails are working. Our site has also use nitropack for caching and I have to mention that we did synchronize with the cloud.

Can you help us with this issue?