Check engine light on 2010 toyota prius with 189k miles. What could it be?

I'll explain this from the beginning how this started so maybe someone could pinpoint what this could be. My check engine light came on about a month ago. I found out that it was my air filter box hose was loose. Which i guess i loosened it on accident when i was changing my air filter. So tightened all that... show more I'll explain this from the beginning how this started so maybe someone could pinpoint what this could be. My check engine light came on about a month ago. I found out that it was my air filter box hose was loose. Which i guess i loosened it on accident when i was changing my air filter. So tightened all that up. Check engine light goes off the next day. Ok about a month or so later. Check engine comes back on. About 20 something different codes show up all leading to either o2 sensor or maf sensor. Well the maf sensor was cleaned with maf sensor cleaner to try that for a few days to see if it would clear, that didnt work. So then i replaced the downstream o2 sensor, didnt work either. So now im either thinking it could be the upstream sensor or maybe the maf sensor has to be replaced. Idk what to do. I got limited funds
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