# plotting – Step size is effectively zero; singularity or stiff system suspected

I am trying to solve four coupled nonlinear differential equations.
But, everytime I am getting
NDSolve::ndsz: At t == 2.0833315360868916`, step size is effectively zero; singularity or stiff system suspected.
I have tried all the possible ways to solve such kind of problem with similar kind of problems available in stack.
I want to get the value of g1,g2,g3 and g4 for large value of t i.e. 1 to 100 but I am getting only for small value of t?
Could you please suggest me some way to sort out the issue?
(Eta) = 0.125;
rg1s = Derivative(1)(u1)(t) – u1(t)u3(t) – 3u1(t)u4(t) + u2(t)u3(t) + 3u2(t)u4(t) + 2(1 + 2(Eta))u1(t)^2 == 0;
rg2s = Derivative(1)(u2)(t) – u2(t)u3(t) – 3u2(t)u4(t) + u1(t)u3(t) + 3u1(t)u4(t) + 2(1 + 2(Eta))u2(t)^2 == 0;
rg3t = Derivative(1)(u3)(t) – 0.5
((u1(t) – u2(t))^2 + u3(t)^2 – 3
u4(t)^2 + 6u3(t)u4(t)) == 0;
rg4t = Derivative(1)(u4)(t) – 0.5
((u1(t) – u2(t))^2 + u3(t)^2 + 5
u4(t)^2 – 2u3(t)u4(t)) == 0;
sol = NDSolve({rg1s, rg2s, rg3t, rg4t, u1(0) == -0.6
0.2, u2(0) == -0.6
0.2, u3(0) == 0.6*0.2, u4(0) == 0.2}, {u1, u2, u3, u4}, {t, 1, 10})

Thank you

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