Simplify doesn't work properly after IgnoreAnal​yticConstr​aints

I tried to use combination of symbols and numbers to get my dynamics. Matlab is considering the same symbols from different matrices as different variables and creating it's own duplicate and hence not actually simplfying the symbolic solution. Can any one help me understand what am I missing. My symbol doesn't have any q1bar , q2 bar, q3 bar but the answer to simplify contains them.

here's my code

syms q1 q2 q3 dq1 dq2 dq3 t1 t2 t3
g  = 9.8; % gravity in downward dir
m  = 0.2;
m1 = 0.2;
m2 = 0.2;
m3 = 0.2;
mf = 0.2;
l1  = 0.07;
l2 = 0.095;
l3 = 0.11;
h = l1+l2+l3;
Jb_sl1 = [0 0 0;0 0 0;-l1/2 0 0;1 0 0;0 0 0;0 0 0];
Jb_sl2 = [0 l2/2 0;0 0 0; -(l2*cos(q2) + l1)/2 0 0;1 0 0;0 0 0;0 1 0];
Jb_sl3 = [0 (l3*cos(q3)+l2)/2 l3/2;0 -l3*sin(q3)/2 0;-(l2*cos(q2+q3)+l1)/2 0 0;1 0 0;0 0 0;0 1 1];
M11 = [m 0 0 0 0 0;0 m 0 0 0 0;0 0 m 0 0 0;0 0 0 0 0 0;0 0 0 0 0 0;0 0 0 0 0 0];
q = [q1;q2;q3];
dq = [dq1;dq2;dq3];
M = simplify((Jb_sl1'*M11*Jb_sl1)+ (Jb_sl2'*M11*Jb_sl2) + (Jb_sl3'*M11*Jb_sl3));
feval(symengine,'simplify',M,'IgnoreAnalyticConstraints')

V = -g*(m1*h + (m2*l1*sin(q1)) + (m3*l2*sin(q1)*sin(q2)) + mf*l3*sin(q1)*sin(q2+q3));
N = simplify([diff(V,q1);diff(V,q2);diff(V,q3)]);
% on differentiating M with respect to q we get C matrix as per given below
C  = sym(zeros(3,3));
 for i = 1:length(q)
     for j = 1:length(q)
         for k = 1:length(q)
              k = 1:length(q)
             C(i,j) = C(i,j) + 1/2*(diff(M(i,j),q(k)) + diff(M(i,k),q(j)) - diff(M(j,k),q(i)))*dq(k);
         end
     end
 end
C = simplify(C);
Torque = [t1;t2;t3];
ddq = simplify(inv(M)*(Torque - N - C*dq))