My subplot images are cut off, why?

My images gets cut off when the function is on steady state, I think the problem comes from step command, because I'm getting [y, t] = step(sys)

informations and I don't know why this cut off automatically when a plot inside a subplot!

clc
clear all
syms s;
format short
%-------------------------------------------------------------------------%
% I)
wn1 = 1; k1 = [0 0 5]; zeta1 = [1.5, 0.7, 0.3];
G1 = tf(k1, [1 2*zeta1(1)*wn1 wn1^2]);
G2 = tf(k1, [1 2*zeta1(2)*wn1 wn1^2]);
G3 = tf(k1, [1 2*zeta1(3)*wn1 wn1^2]);
%-------------------------------------------------------------------------%
% II)
wn2 = 10; k2 = [0 0 5]; zeta2 = [1.5, 0.7, 0.3];
G4 = tf(k2, [1 2*zeta2(1)*wn2 wn2^2]);
G5 = tf(k2, [1 2*zeta2(2)*wn2 wn2^2]);
G6 = tf(k2, [1 2*zeta2(3)*wn2 wn2^2]);
%-------------------------------------------------------------------------%
lw = 3; %linewidth

ax1 = subplot(2,1,1); %i
    hold on
    [a,b] = step(G1); 
        plot(b, squeeze(a), 'LineWidth', lw, 'Color', 'r');
    [a1,b1] = step(G2); 
        plot(b1, squeeze(a1), 'LineWidth', lw, 'Color', 'g');
    [a2,b2] = step(G3); 
        plot(b2, squeeze(a2), 'LineWidth', lw, 'Color', 'b');
    hold off
    grid on
    
ax2 = subplot(2,1,2); %ii
    hold on
    [a3,b3] = step(G4); 
        plot(b3, squeeze(a3), 'LineWidth', lw, 'Color', 'r');
    [a4,b4] = step(G5); 
        plot(b4, squeeze(a4), 'LineWidth', lw, 'Color', 'g');
    [a5,b5] = step(G6); 
        plot(b5, squeeze(a5), 'LineWidth', lw, 'Color', 'b');
    hold off
    grid on

Answer 1

[Leandro de Oliveira]

SOLVED!

Actually is a simple thing, when whe plot getting step parameters we have to tell step xlim that we want the Tfinal, otherwise the step will automatically choose xlim as the stead state (I guess), so the correct way to get step parameter before plot is:

G = sys
[y, t] = step(sys, Tfinal) %Tfinal here commands plot xlim final value (higher hierarchy)
plot(t, squeeze(y))
xlim([0 Tfinal])