Question: I need to debug the Error of parameters' must be specified as a list of unique unassigned names

  restart:

  interface(rtablesize=10):

  local gamma:local pi:

if false then
 theta := 0.987: betae := 0.231: betay := 0.112: rho := 0.17: muh := 0.05 : sigma2 := 0.0411: sigma1 := 0.212: alpha1 := 0.111: alpha2 := 0.131 : eta := 0.134: thetaa := 0.7271: betaf := 0.00954: betah := 0.008220: gamma := 0.0012: mua := 0.0023: sigma3 := 0.203: d := 0.451: z := 0.072:
end if:

#
# D() is Maple's differential operator replated D(T)
# with DD(T) in the following to avoid confusion
#

  ODE1 := diff(B(T), T) = theta-(betae*C(T)+betay*rho*G(T))*B(T)-muh*B(T)+sigma2*E(T):
  ODE2 := diff(C(T), T) = (betae*C(T)+betay*rho*G(T))*B(T)-(muh+sigma1+alpha1)*C(T):
  ODE3 := diff(E(T), T) = sigma1*C(T)-(muh+sigma2)*E(T):
  ODE4 := diff(G(T), T) = alpha1*C(T)+alpha2*K(T)-eta*G(T):
  ODE5 :=  diff(H(T), T) = thetaa-(betaf*H(T)+betah*gamma*G(T))*H(T)-mua*H(T)+sigma3*K(T):
  ODE6 :=  diff(J(T), T) = (betaf*H(T)+betah*gamma*G(T))*H(T)-(mua+d+z+alpha2)*J(T):
  ODE7 :=  diff(K(T), T) = z*J(T)-(mua+sigma3)*K(T):

 
if false then
  B0 := 100: C0 := 60: E0 := 50: G0 := 55: H0 := 80: J0 := 80: K0 := 80:  

end if:

# system + ic


sys := { ODE1, ODE2, ODE3, ODE4, ODE5, ODE6, ODE7,
                   B(0) = B0, C(0) = C0, E(0) = E0, G(0) = G0, H(0) = H0, J(0) = J0, K(0) = K0

                 }:

params := convert(indets(sys, name) minus {T}, list);

#
# Solve system
#
  ans := dsolve( { ODE1, ODE2, ODE3, ODE4, ODE5, ODE6, ODE7,
                   B(0) = B0, C(0) = C0, E(0) = E0, G(0) = G0, H(0) = H0, J(0) = J0, K(0) = K0
               
                 },
                 parameters = params,
                 numeric
               );

Error, (in dsolve/numeric) 'parameters' must be specified as a list of unique unassigned names