Draw Call increase 5x after bake lightning

Hello everyone,
As what i do before, after i baking lightmap, the drawcall decrease but currently when i baking lightmap complete, the draw call up to 5x !!
So, am i wrong in Lightning settings or bake Lightmap will increase drawcall ?
Here is before bake, draw call max is 23 in everywhere on the map

And here after bake with 1 direction light, Soft Shadow, Very High Resolution

@GunLengend 我知道为什么会造成这种情况,我也发生了。后来不停的测试发现是烘培的对应的图集设置太小了,所有导致烘培的信息被拆分成很多个,导致烘培贴图不能合并,DC增加。