Can't sieve reply to certain received E-Mails by a predefined E-Mail?

Question

Our hosting provider supports sieve E-Mail rules, and they are perfectly working, e.g., to move received E-Mails based on a Regex.

But now, if someone writes to office@mydomain.com, then we must reply with an E-Mail like "Thank you for your E-Mail" to explicitly confirm that the Server received the message.

Does Sieve not have a simple "Answer by E-Mail" function by default?

As a workaround, I have tried to use the vacation rule, but it never sends an answer. And we should confirm each message, and we can not set :days 0 if the hosting provider does not allow it.

In case it helps, I have added our Sieve rule below. After all, it would be much better to send one email per day than never :-)

Does anybody know a solution?

if allof (header :contains "to" "office@mydomain.com")
{
    vacation 
    :days 1 
    :subject "Thank you for your message!" 
    :from "NoReply@mydomain.com" 
    text:
    Here, we have the email message
    .
    ;
    stop;
}