Error using algebraic constraint block in simulink

I have attached the DAE diagram although this is not full system diagram but i am facing error in algebraic constraint block and it gives the following error: " Simulink cannot solve the algebraic loop containing 'untitled/Subsystem/Algebraic Constraint/Initial Guess' at time 0.0 using the TrustRegion-based algorithm due to one of the following reasons: the model is ill-defined i.e., the system equations do not have a solution; or the nonlinear equation solver failed to converge due to numerical issues. To rule out solver convergence as the cause of this error, either a) switch to LineSearch-based algorithm using set_param('untitled','AlgebraicLoopSolver','LineSearch') b) reducing the ode23tb solver RelTol parameter so that the solver takes smaller time steps. If the error persists in spite of the above changes, then the model is likely ill-defined and requires modification."

Please help in solving this problem.