Making in-app store purchase

Hello,

I am a beginning jazz piano student and a new user to this software, having just bought the Mac and iOS versions over the past 24 hours. I have managed to make the Chord Scales and Piano Chords purchases without a hitch on my iPhone, but for some reason I can only make the Chord Scales purchase on my Mac without a problem (the button in the store has changed to "Installed" and everything works fine there).

Every time I try and purchase the Piano Chords functionality, however, the "Buy" button changes to "Installing..." and stays there, every time. I have tried three times now. I hope I am not charged for all three. I am also not sure (and I am not told in the software) how long it takes to install. I am on a fibreoptic broadband connection, so I shouldn't imagine it would take long.

Perhaps including some sort of download progress bar may help us to know whether the software is actually being installed or whether it is just stuck. The rest of the program runs fine and I can still use it even though, for some reason, it cannot install the Piano Chords.

Please advise me on what I can do to make this work. Thank you for your time and assistance.

A little bit of additional information: when I go to the Store after opening up the program, after logging in with my Apple ID the software tells me "Thank you for purchasing Chord Scales" - but it does not tell me "Thank you for purchasing Piano Chords". This leads me to believe the payment is not happening, and the install is not completing, for some reason.