Is it possible to validate the data to avoid duplication?

Hi,

I presume that you would like to limit the jotform submissions in case someone already submitted the jotform, avoiding duplication. For this you should take a look at these 2 guides

How to Set Unique Submissions on a Form

How to set Form Limits Based on a Unique Question

Do let us know if this is or is not what you were looking for and please let us know if you have any further questions if it is.

Best Regards,
Ben