LM26420-Q1: Low Phase Margin with 1V & 0.7amps....

Greetings,

When I run this part through Webench , with 3.3v input, 1.0v out and 0.7amps, the phase margin drops below 35 and Webench fails with, "Design update failed. This design is not stable due phase margin either smaller than 35 or greater than 120".  How accurate is this Webench sim, and is there any way to improve the phase margin with this part?

Thanks