Slow internet

For the last several days, my internet is way slower than it should be. Streaming content is extremely blurry, online gaming has been impossible, and net speed tests are ranging from 5-80 mb/s for wireless connections and 150-250 mb/s for wired connections. I'm supposed to be getting nearly 1gb+ but have realistically usually had around 700-800mb/s. I have done restarts numerous times on the router. I've tried different ethernet cables for the wired connections. I've power cycled every device I could think of and seen no improvement. The AI assistant, when I've called, has stated that maintenance was recently done in my area but all it does to try to help is initiate restarts. When I check network speeds through the xfinity app, it's suggesting I'm operating at 116% capacity for my internet speeds and all devices should have a strong signal but they just aren't performing that way. What else can be done? Obviously the AI assistant can't help me.