I need to tweak for the symmetryPlane boundary condition

/2elbow-LT-for-holly$ cat log.icoFoam
/*---------------------------------------------------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  4.1                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
Build  : 4.1
Exec   : icoFoam
Date   : Nov 13 2018
Time   : 21:33:59
Host   : "caelinux"
PID    : 15652
Case   : /home/caelinux/OpenFOAM/caelinux-4.1/run/tutorials/incompressible/icoFoam/2elbow-LT-for-holly
nProcs : 1
sigFpe : Enabling floating point exception trapping (FOAM_SIGFPE).
fileModificationChecking : Monitoring run-time modified files using timeStampMaster
allowSystemOperations : Allowing user-supplied system call operations

// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //
Create time

Create mesh for time = 0


PISO: Operating solver in PISO mode

Reading transportProperties

Reading field p

AMI: Creating addressing and weights between 40 source faces and 5 target faces
AMI: Patch source sum(weights) min/max/average = 1, 1, 1
AMI: Patch target sum(weights) min/max/average = 1, 1, 1
Reading field U

Reading/calculating face flux field phi


Starting time loop

Time = 0.05

Courant Number mean: 0.00886767 max: 2.5
smoothSolver:  Solving for Ux, Initial residual = 1, Final residual = 1.26206e-11, No Iterations 1
smoothSolver:  Solving for Uy, Initial residual = 0, Final residual = 0, No Iterations 0
smoothSolver:  Solving for Uz, Initial residual = 1, Final residual = 1.26206e-11, No Iterations 1


--> FOAM FATAL ERROR:
Continuity error cannot be removed by adjusting the outflow.
Please check the velocity boundary conditions and/or run potentialFoam to initialise the outflow.
Total flux              : 2.63698e+08
Specified mass inflow   : 1.3e+07
Specified mass outflow  : 0
Adjustable mass outflow : 0


    From function bool Foam::adjustPhi(Foam::surfaceScalarField&, const volVectorField&, Foam::volScalarField&)
    in file cfdTools/general/adjustPhi/adjustPhi.C at line 107.

FOAM exiting

------------------------------------------------------------------
fvSolution:
----------------------------------------------------------------


/2elbow-LT-for-holly/system$ cat fvSolution
/*--------------------------------*- C++ -*----------------------------------*\
| =========                 |                                                 |
| \\      /  F ield         | OpenFOAM: The Open Source CFD Toolbox           |
|  \\    /   O peration     | Version:  4.1                                   |
|   \\  /    A nd           | Web:      www.OpenFOAM.org                      |
|    \\/     M anipulation  |                                                 |
\*---------------------------------------------------------------------------*/
FoamFile
{
    version     2.0;
    format      ascii;
    class       dictionary;
    location    "system";
    object      fvSolution;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

solvers
{
    p
    {
        solver          PCG;
        preconditioner  DIC;
        tolerance       1e-06;
        relTol          0.05;
    }

    pFinal
    {
        $p;
        relTol          0;
    }

    U
    {
        solver          smoothSolver;
        smoother        symGaussSeidel;
        tolerance       1e-05;
        relTol          0;
    }
}

PISO
{
    nCorrectors     2;
    nNonOrthogonalCorrectors 2;
    pRefCell  0;
    pRefValue 0;
}


// ************************************************************************* //