Pour bleach in every single drain and each toilet let the bleach sit as long as possible to kill off larvae or drain eggs. Drains are a breeding ground for them to lay their eggs. Dry every pillow in the dryer for 15 min on high heat with wet washcloths soaked in peroxide. Peroxide is the other bleach. Wipe down all surfaces with bleach. Look for dirt in places you don’t notice everyday like the bottoms of garbage cans in your house, next to the stove and fridge. (You might have to pull them out and look for old drips or spilled sugar) Spinkle salt on all your carpets and leave them for a couple days then vacuum it all up. Salt is dehydrating for them to lay eggs. Air out your house and wipe down arms on chairs and furniture for fungus. This sounds like a lot of work but it only takes a couple hours and will eliminate fruit flies and gnats. Hope this helps.
