Perform Insert action once the PR is Approved

Hi There,

I need to insert records in my custome table once the PR is approved.

I tried to write the login in modifiedfield method of PurchReqTable but its  not working.

I followed below link but i could find the exact method in which PR status is getting updated to Approved.

https://community.dynamics.com/ax/f/33/t/164932

Can you please guide me the class and method name which is called when updating PR status to approved.

Thanks,