usb stick unsupported on the display

My Yamaha CD-S300 CD player is showing UNSUPPORTED on the display when I insert a USB stick, no matter what format it has. It worked 1 year ago, but now not workig any more. What can I do to solve it?

Thank you!

crwdns2934089:0crwdne2934089:0 crwdns2934093:0crwdne2934093:0

crwdns2934109:0crwdne2934109:0

crwdns2889612:0crwdne2889612:0 0
crwdns2934285:0crwdne2934285:0