Assuming that the surround has just separated from the driver cone, and not ripped the cone off with it, it is a 10 second job to re-glue it on.
I highly recommend this speaker glue: Speaker Repair Adhesive, Foam Kits, Recone Kits, Speaker Grill Cloth, MI-3035 (simplyspeakers.com)
I highly recommend this speaker glue: Speaker Repair Adhesive, Foam Kits, Recone Kits, Speaker Grill Cloth, MI-3035 (simplyspeakers.com)