FDTD Sulivan's Book Error ?

I have interest in implementing 2D FDTD with PML for free space. I used Sulivan's code but, I found the Electric field does not converge into zero. The remaining wave is more than simulation with LIAO ABC.

Could you let me know exactly what is the problem in his code ?

My frined could you check this link after some time it becomes zero I think aroun 285 something in this link you will find the program that i ahev written from the same book but the problem is actually with the 3D PML code it become unsatbale if you can find any solutionm to this problem pleaese also let us know see uou soon
the link that i mentioned is this
https://www.edaboard.com/ftopic176087.html

you can write to me as well my mail is sadabat2004@yahoo.com