Formit span hook error

Hello I’m getting this error reports when trying to send an email from a form build inside formit:
everything was working fine until today.

[2020-06-11 15:50:48] (ERROR @ /home/user/public_html/core/model/modx/rest/modrestclient.class.php : 245) Could not connect to provider at:
[2020-06-11 15:50:48] (ERROR @ /home/user/public_html/core/components/formit/src/FormIt/Hook/Autoresponder.php : 201) [FormIt] An error occurred while trying to send
                      the auto-responder email: Could not instantiate mail function.

Any guide please?

It seems like the ‘spam’-hook tried to check the email-address but the call to the api failed:

Maybe the fix in this forum post still applies.