Received random salary a year later

i have received some amount today from Cognizant as salary today. But the catch is that I worked in Cognizant a year ago ( left around Sept 2022 ) . And even joined another company which i resigned from this july. Right now i am on a break from work unemployed due to medical reasons. And i really got some amount today as salary. I am confused - my F&F was settled last year only . can i contact someone at Cognizant ? did they do a mistake ?