I have an invasion going
Might be "cluster flies" - see if these help.
Try this, take a clear gallon storage bag, fill with water, put in a couple of shiny pennies, tie shut and hang up by the back door. It bothers their eyes. saw this done at an out door restaurant.😃
Go to Home Depot and buy "Rescue" Disposable Fly Trap....just add water and it smells mildly similar to manure when sun warms up bag. We had a real bad fly problem near our trash bins; hanging the "Rescue" bag near by has eliminated the flies. Flies now just fly straight over to the fly trap. Cost is $4.98 before tax, and well worth the cost considering the HUGE amount of flies the trap captures. I have been using this product for several years now, and the fly trap never disappoints me. This "Rescue" product is well worth checking out per my opinion.......
I’ve used a similar product for wasps/hornets and it works great. The old fashioned flypaper strips work well too.
Have also used the Fly trap for outside with great success. When they get inside I found "Victor Fly Magnet" . Glue trap that sticks on a window with a narrow adhesive strip. "Ortho Home Defense Fly Bait Decal" has an attractant coating that kills flies within a minute of eating. Can be applied high away from pets and children.
Thank you for your suggestions, I will try them . 😊