Hi Efra,

There is OOB Business rule on change_request table, Business rule name : State model - Can change state?

https://YourServicenowinstance.service-now.com/sys_script.do?sys_id=f3fbe0d8cb200200d71cb9c0c24c9c93&sysparm_record_target=sys_script&sysparm_record_row=40&sysparm_record_rows=49&sysparm_record_list=collection%3Dchange_request%5EORcollectionINchange_request%2Ctask%5Ecollection%3Dchange_request%5EORDERBYname

Please mark as correct/helpful if the above answer is solve/helps your issues.

Regards,

Harish Murikinati.