misunderstanding of Voltage output of a 3-phase rectifier
Your V2 polarity is backwards. You want the minus side on ground.

Your circuit is probably working. As it is, both of your outputs are plotting positive, and all you see is ripple. We need to see your plot axis labels to know for sure.

It works in CircuitLab (guessing at what you think that it should do)







simulate this circuit &ndash; Schematic created using CircuitLab



Edit: Plot with left ground removed. DKNguyen is correct, it works much better without the ground on the left. Only a few tenths of a volt of ripple.