How to get the transaction_id of hr_api_transactions table in the user hook for validation purpose?

In SSHR, while launching an EIT . I want to validate if the EIT has already been launched for approval.

i.e. If it has already been approved and loaded in the EIT table then using a user hook , I can validate and stop the user from launching it for approval.

But in case he has already launched for approval and it is waiting for approval then It is only existing in hr_api_transactions tables and does not exist in the base table.

In such a situation the employee should not be able to launch the EIT again.

In the user hook validation , I do not have the transaction_id.