AES Encryption – without IV

Hi,

We are trying to encrypt a text with a secret key – ‘without passing the IV’. Referring to https://community.sap.com/t5/application-development-blog-posts/aes-encryption-in-abap/ba-p/13401465

we were able to arrive at the logic along with the IV, however without the IV the correct encoding doesnt take place.  

Any pointers on how we can achieve this will be helpful.