@rattler21 posted:Duct tape or two inch wide packaging tape ought to keep it closed. John
All tape eventually dies and leaves a gummy residue when it finally comes off. Besides it will look terrible. I'm sure the OP is not after that patched with tape look. I have used both white glue and yellow waterproof wood glue which results in an invisible repair. After applying a thin uniform coat of the glue along the box glue tab I then clamp it between two boards for a couple of hours. You won't be able to tell it was repaired. I have also used CA on occasion with good invisible results. j