I usually find that simulations converge better with ideal gas law. Go to the fluid pane and set the density to “Ideal Gas Law”, and for Mol. Weight, use a constant value of 29 kg/kmol. The first P0 residual is very low (~1E-8), so set the fluid normalization (in the Numerics pane) to 0. Start with a time step of 1E-4 s and it should move forward.
Please verify your initial particle setup, you are asking for 25000 particles in each region, which is more than can fit.