Hello Pradip,
In 4.2.1 beta there are hooks (
https://www.imunify360.com/blog/beta-imunify360-released), with the help of them you can make your handler and send a letter from it.
We are preparing the information on automatic account lockout, where we will tell you how to make it out of hooks.
Please let us know if you have any questions.
Thanks in advance!