that type of lock is prone to stiffness, check it pushes in and returns out cleanly
some wd may free it,
if it doesn`t come fully out the mechanisn maybe prevented from allowing the key to lock it,, lift hatch remove the plastic trim, flick the lock lever manually to lock and see if the key unlocks it, , check the rod is attatched first and the locking motor is working, sure , if you don`t have a working key for the bootlock you will need 1 for locking manually, otherwise fix the remote function