The flies are getting in around tiny openings around the screens. Tape around the screens will stop them.
There are several species of the green bottle fly.
So, I have had a some "visitors" for some time now and I'm losing my patience with them so I need help. Every night I get these weird flying insects in my room as far as I know they are only in my room most likely because I often have my windows open, but I do have screens on said windows and the bugs are too big to go through them. They're smaller than a fly but bigger than a gnat, they have thin bodies and narrow wings that point parallel to their bodies, some are green and some are black the black ones are bigger and easier to catch the green ones are pretty fast. They're not like a swarm or an infestation just like 3 or 4 every night I usually just kill them and move on but I'm a real germiphobe and I freak out when they touch me I'm not scared just grossed out. I'm working on getting a picture of the one green one that's left.
Also, I have like no idea where to categorize this.