Check the validity of reinforcement geometry
Reinforcement creation or modification can result in invalid reinforcement geometry. For example, too big bending radius can cause invalid reinforcement geometry. If a model contains a reinforcement with invalid geometry, the reinforcement is not shown in the drawings. The reinforcement becomes visible and the drawings are updated when the geometry is corrected.
If a rebar set leg face or leg surface is shown in red in the model, it means that the geometry of some bars in the rebar set is not valid. Check and fix the properties of the rebar set (for example, the bending radius) or the leg face or leg surface.