We are experiencing a delay/ latency in the email reception due to the general behavior of email sync, which is delaying the case creation. By the time the case creation is done in MS Dynamics, the client's existing system is able to receive tickets, create case, forward the email and receive an acknowledgement email as well on that case.
I had created a ticket with Microsoft to address this but they explained me that they won't be able to do much than to suggest me to submit a feedback for the same. Kindly address this soon.