Twin Sleep Regression

Our twins just started what we believe to be the dreaded 4 month sleep regression. They’re fighting naps, and when they do nap it’s typically only around 10-20 minutes if they’re not being held. With that being said, they weren’t the greatest sleepers before, but they could nap by themselves and for longer periods of time. What tips, if any, do you have to get through this and/or make this easier?