I'm using FPV Digital System mode connected to my air unit.
The menus vanish as soon as I have VTX connectivity. If I disconnect, or power off my Drone, the Menu re-appears.
How do I get into the menu during flight??

I figured it out. I had to activate the Caddx Vista as well, not just the Goggles.. I hooked the Vista up to my laptop running DJI Assistant 2 FPV series and logged in as myself. I powered on the drone/vista and DJIA2 found it. I was able to Activate it.. And upgrade the firmware.. All is good now!

Hello there IPvFletch. I am sorry for the trouble this has caused before and it is great to know that you were able to sort the issue out and for sharing how you have rectified the said issue. Have a safe and a happy flying always.