existence "inf" and "NaN" in solve in matlab

existence "inf" and "NaN" in solve in matlab

I'm trying to run below problem,that exist one loop for solve equations,
but the answer is NaN or inf/inf
A=9272.699404; %data
al=0.8156; %data
be=0.0062577;
fi=15.4935;
de=.05;
m=101877;
a=3.5323;
b=0.00398;
l1(1)=-370.713;
l2(1)= 68;
x(1)=1550000000;
r(1)=1549000000;
for t=1:100;
x(t+1)=(A*(((fi*exp(be*x(t)-de*t))/(A*al*l1(t)+ A*al*l2(t))).^(1/(al
-1))).^al)/exp(be*x(t))+x(t); %equations
l1(t+1)=(m*(m - a*r(t) + l1(t)*r(t)*exp(de*t)))/(2*b*r(t)^3*exp(de*t))+l1(t);
l2(t+1)=(A*be*l1(t)*(((fi*exp(be*x(t)))/(A*al*l1(t)*exp(de*t) +
A*al*l2(t)*exp(de*t)))^(1/(al - 1)))^al)/exp(be*x(t)) +
(A*be*l2(t)*(((fi*exp(be*x(t)))/(A*al*l1(t)*exp(de*t) +
A*al*l2(t)*exp(de*t)))^(1/(al - 1)))^al)/exp(be*x(t))+l2(t);
r(t+1)=(A*(((fi*exp(be*x(t)))/(A*al*l1(t)*exp(de*t) +
A*al*l2(t)*exp(de*t)))^(1/(al - 1)))^al)/exp(be*x(t)) + (m - a*r(t)+
l1(t)*r(t)*exp(de*t))/(2*b*r(t))+r(t);
qstar(t)=(-(m -a*r(t) +l1(t)*r(t)*exp(de*t))/(2*b*r(t)));
end
x % arrive this