I live in an apartment and the AC they have installed has a condensate
pan below the coils that drip from condensation. The drain for the pan
is located on the side of the pan towards the bottom but there is a
slight lip allowing about 1/6" of water to remain in the pan without
draining. I have been told by the maintenance people that this is
normal and to be expected, however I am beginning to smell mildew and
the insulation on the inside of the unit is filthy.

Can someone please let me know how I should proceed with this
situation?

Thanks