There could be several reasons for a flickering light issue in Unity. Here are few common causes:
Z-Fighting: This phenomenon happens when two (or more) objects occupy the same space and the engine cannot decide which one should be drawn in front. When this happens to lights, it can cause a flickering effect.
Shader Issues: Incorrect shader settings or incompatible shaders may also lead to light flickering problems.
Lightmap Settings: Improper Lightmap settings or discrepancies between static and dynamic objects' illumination can result in flickering.
Precision Issues: This occurs particularly when dealing with very large scenes due to floating-point precision errors.
Here are some resolutions based on the possible causes:
For Shader Issues:
For Lightmap Settings:
For Precision Issues: