Uninstalling problem

A friend was using my home macbook OS 10.15.2 and accidentally installed Sophos Anti-Virus onto it. I have no use for the app and have been trying to uninstall it without any success. I use the Remove Sophos Endpoint tool and it says removal is successful but when I recheck my Mac a day or two later it the app is installed again. I've gone through this process about 3-4 times without any success. Each time the app just shows up again. Can anyone provide some guidance on how to fully get rid of it?