Macbook won't recognize Galaxy S3 as usb device

[AC Question]

I just bought an s3 today. Was using an S7 with Android File Transfer with no issues. When I try to connect my S3 it charges but doesn't allow the option to enter usb mode. Android File Transfer keeps telling me to connect a device (even though it's connected) I've tried checking/unchecking usb debugging and the drop down menu doesn't give me the option of entering usb mode/set up as media device. Once again, I had been using a Galaxy S7 on the same macbook running the same OS with no issues.