Minecraft worked fine yesterday with the old launcher but wont launch today with the new launcher that was 'surprised' onto me. Just stays stuck on 'preparing', rather have the old launcher back that worked!

What I expected to happen was...:
When I pressed Play for the launcher to launch the game/

What actually happened was...:
When I pressed Play the play button turned into a loading bar and displayed 'preparing' but never gets any further. (Its been 20 mins. or more now)

Steps to Reproduce:
1.Start Launcher
2.Press play

Things I have Tried:
Restarting launcher
Restarting computer
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