Put a dish of sugar water on a counter. They should congregate in it and drown. This works for fruit flies and should work for your critters too. You will need to do this a few times, especially after any eggs that may be there, hatch.
I tried the diy taps. They didn't work. Now I use this https://amzn.to/2D28C3W
If they are in your drain, you'll need to clean that. I put ice cubs down the sink and squirted some dish soap in. Cover one drain and run water in the other one to run the garbage disposal. The suds fill up the drain to get all of the bugs.
Ahhh I had this problem and bought a product that is supposed to get rid of them. I narrowed it down to my bathtub drain..(they feed on the sludge in drain ughh!! )So I was reading reviews on the product I bought and one person said that they thought it (the product) actually clogged the drain. My thoughts were to run a drain cleaner down first so I did. I believe it was a DRANO product, gel, made for tough clogs. I poured 1/2 a large bottle down the drain, let it sit a couple of hours and then flushed it with boiling water...no more drain flies! I have the product in my closet (just in case) but it has been a couple of months and no drain flies/moths.