Logitech keyboard & mouse won't connect on login screen

[Zoom7000]

After my long standing PC that I purchased back in 2014 died over the summer (btw, thanks @VeryPC_Colin_M for a true workhorse of a machine that did way past it's time!) I have temporarily decided to switch over to macOS using my 2019 16" MacBook Pro, until I decide where to go next...

 

I'm using the MacBook docked to my dual monitor setup with the Logitech MX Keys and MX Master 3 connected via Bluetooth. When I plug the USB-C connectors in, the MacBook boots up automatically. However, I have one very annoying issue in that when I boot up the MacBook connected to my monitors with the lid closed, the bluetooth devices will not respond at all. I have to open the lid and type the password on the built in keyboard. Once macOS (Big Sur) boots up, the keyboard and mouse connect seamlessly without any issues.

 

I know I can lift the lid, but just wondered if there was a way to get it to work seamlessly? The Apple Magic Keyboard and Magic Mouse (both I have are version 1) work seamlessly. It's just the Logitech devices that won't connect.

[Zoom7000]

For anyone else having this issue, here's the reason from a post on reddit:

 

You probably have FileVault enabled...Bluetooth devices will only connect after login when FileVault is enabled.

 

https://support.logi.com/hc/en-001/articles/360037899233

 

I'll have to try the USB receiver. Hope it'll will work via the USB-C hub that I'm using!