iTunes Purchases not showing in on iPhone or iTunes Purchase History

I have just upgraded to an iPhone Xr, after updating the new phone from iCloud Back up I noticed some songs were missing in the Music app from the update. For example, I purchased "The Complete Smiths" which contains 100+ songs but my phone is only showing 3 songs. So, I went to Purchase History in the iTunes app and in there it is only showing that I purchased the 3 songs on my phone when I bought the full album.

This happens for multiple purchases, many missing songs from albums, all of which are still available in the store.

Anybody got any ideas how to rectify this issue, please?