Message can not be sent – All configurations are correct

Hi support-team,

i’m already really frustrated. For one of my clients i use the Avada-theme and setup two contact forms on the link sent above.
https://hausarzt-ditzingen.de/rezeptbestellung/

I was in touch with the Avada-Support already and with the support of my hosting, nobody can find the problem why messages from these both contact forms cannot be sent. What’s really strange too is the fact that about two weeks ago i could sent the messages and everything worked fine.

At this moment i tried it with the wp mail smtp-plugin, i configured this one too successfully and checked the email-sending, it worked for the wordpress@… email. But messages from contact form can still not be send.

I don’t have any more ideas what i can do? :-((

Thanks for help in advance.
Hans

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