battery that has leaked into the box

Hello my problem with this gizmo is the battery that has leaked into the box and the metal connectors have melted

I sanded the connectors but it did not work

Is there a way to fix it?

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

crwdns2934109:0crwdne2934109:0

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