Garageband - The file couldn’t be opened because it isn’t in the correct format

I've just performed a clean install and GarageBand gave me this message when trying to create a new file:

"The file couldn’t be opened because it isn’t in the correct format.

The file might be corrupted, truncated, or in an unexpected format."

Secondly, I have also noticed that when creating a new file there is only Podcast and Movie available (screenshot attached).

Lastly, When trying to open an existing file it says:

"Can't Open the Song: This song requires a newer version of GarageBand.

Please update to the latest version of GarageBand before opening this song."

... but I already have v.6.0.5

Any help will be gladly appreciated. Many thanks in advance.