Cannot sync Google Drive between MacBook and iPhone app

On my iPhone I installed GoogleDrive ‘Drive’ app.

On my MacBook I installed Backup and sync from Google.app, which has created a ~/google-drive/ folder.

I have set the account to my@gmail.com and put some files and folders in it.

On my iPhone app I also set the account to my@gmail.com. I can see some of the older folders. These appear to match that on my MacBook, although the contained files are out of date. I can also see a file dated about a week ago which I have since deleted on my MacBook.

Files I have added/removed within the last 24 hours on my MacBook simply don’t register on the iPhone.

It seems clear that the devices are out of sync. But they’re both connected to my apartment’s Wi-Fi.

I can’t find any sync button / menuitem.

This is very frustrating.

What is going on? I was hoping that Google Drive would be my solution for distributed storage.