Unable to get tutorial guided turret working.

Hi, I have been following a tutorial on creating a tower defense game.

However I ran into an issue in which the object I'm building (a turret), is not working as it should.

In my case, the turret simply tilts to the side and not fire upon pressing play and remains there as shown in the image below.



I have attached a file with the assets that I have used.
This includes the "MissileCannon" as the turret, the "Missile" as the projectile and MissileTurret and Projectile_Missile scripts accordingly.

Would greatly appreciate it if someone could help me pinpoint where have I gone wrong.
Thanks!

 

where did the mesh assets come from?