How To Customize validation in Input Field

i have Done validation of required field and email validation 

as you can u see in the form ,now i want to customize the validation firstname and last name should be greate than 3 characters,

Above screen is my logic

and i am assinging the values as 

But its is not validating the screen ,what i am doing wrong
Hi Tarun,

Please share oml file, pictures are not clear.

Once you assign the valid property to false, you still go further to the createorupdate action, so it doesn't take into account your validation (of the if statement).

Instead of going from your assign to the create or update action, go to the valid condition (the if above).