Black fly help me out please

I went into my grow room( im growing ffof soil) and i saw a huge black fly like the big ones red eyes . i hit it and it died but it dropped larva and some smaller black flies , ive been struggaling with a littel pest issue thinking it was fungus gnats but now im wondering if it could be these littler fuckers. dropping larva in my soil n killing my plants any thoughts on this?

Cover the soil with a piece of white, printer paper. Cut a hole for the plant of course. This will prevent the gnats, flies, etc. It will also keep the 'green stuff' from growing on the top of your soil.

You can try sprinkling cinnamon too.... I am trying that natural remedy.. 100% cleaned up now... but a massive pain in the ass to deal with any bugs..