The lock in the boot of my 1997 vw polo just spins as I try and unlock it?

Yesterday I repaired the drivers side lock on my vw polo and today the boot lock has busted!

The car has central locking and up until today I had to unlock the car from the drivers or passenger door and then unlock the boot using the key.

When I tried this today the lock just kept spinning.
Has anyone else had a similar problem and/or have any idea how to fix it, and if it will be a similar job to the drivers side lock?

Also, is there a way of opening the boot from the inside?

Its dark now so can't get a proper look till the morning but hopefully I'll be ale to sort this out myself!