Cognizant — job/career

I had a horrible experience working in this company. I used to work as csr in voya one of the processes of cognizant situated in hanston square bldg. I reached out with my immediate team leader and resigned and yet after 2weeks i received a return to work notice and allegations that i committed absences and job abandonment. Therefore, i conclude that the supervisor i talked to did not forward my resignation letter and medical certificates to the human resources-talent management. Such a shame for the aspiring world-class company. I would never ever reccommend this company to anyone. People, culture, and working environment in cognizant hanston square are all chaos and unpleasant.