I have created a power automate flow, below is the trigger action

but sometimes it is behaving strange, some time it is triggering the flow if the new emails arrive in sent item but sometimes it is skipping some mails.
if we are sending bulk emails at a time it is skipping some emails to trigger the flow, and also, we are using web shared mailbox for replying on the emails.
if we have kept open an email for 2-3 min in web browser after that if we are sending it, flow is not triggering for those emails also
it is urgent I need help with this issue.