Not getting mail when new ticket is created

[Shanthini]

Hi,

I am an administrator of OTRS. I have created a search template to see the new tickets in my queue.
Also whenever a new ticket is created, I get a mail saying Hi Admin, there is a new ticket.

But sometimes I don't get a mail when a new ticket is created. Also, the new ticket doesn't appear in my search template when I choose it.
Kindly let me know why it is happening and where exactly in OTRS I can check the reason for this error.

Thanks in advance.

With regards,
Esther Shanthini.