Wipro — Wipro off-boarding not providing experience letter

I was a former Wipro employee. My Employee Id was 152751. I need an experience letter from Wipro in a format my attorney requested to initiate the green card process. I already have a previous experience letter from Wipro but that is not in the format acceptable by immigration.

So I contacted letters.[protected]@wipro.com to provide me with the letter in the immigration format. They said
"In your case we understand that you were already issued with experience letter, hence we may redraft the same contents in the earlier issued experience letter in immigration format (as per format we include “on full time basis”) and share with you. No other additional details can be included to earlier issued letter."

After many emails finally, they issued me a letter which is the SAME as the previously issued experience letter and NOT in the immigration format. I have been contacting letters.[protected]@wipro.com to provide me the letter in the requested format which they originally agreed but there is no response.

So I am seeking help in this regard. Please do the needful.