This warning is a result of applying supports in a direction to nodes that are already held in that direction by other means. Typically, this occurs at supports applied to macroelements connected through master-slave connections (e.g., 2 blocks next to each other, supported from bottom), or when shells are supported in a direction not perpendicular to their thickness (then, the implicit master-slave in depth direction and the support act in the same direction).

A boundary conditions' conflict can also occur on a line (point) shared by 2 surfaces (lines) with boundary conditions applied. In that situation, you may need to apply the combined condition explicitely to the line (point), if the 2 conditions are not identical.