Week 10 - Simulating Combustion of Natural Gas.

I am getting the below mentioned warning

Warning: The use of axis boundary conditions is not appropriate for a 2D/3D flow problem. Please consider changing the zone type to symmetry or wall, or the problem to axisymmetric. Warning: The use of axis boundary conditions is not appropriate for a 2D/3D flow problem. Please consider changing the zone type to symmetry or wall, or the problem to axisymmetric.