Automated email through “Mailto:” is too slow

Hello!

We have set up contact forms with first contact autoresponse HTML emails in the “reply-to” section on the completion of form filling. But most of the response mail sent via the contact form falls under the spam folder and also the response time of these automated mail via contact form backend after the form submission is too slow. As it takes more than 7-8 hours on each submission.

Please guide me on what went wrong and how can I increase the speed of the automated response time.

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