Yeah, Ive been down that road when my 100 Mbps service dropped into the high 80s. All it took was filling out a complaint form on the FCC website and Spectrum was falling all over each other to get to my house and correct it (including a supervisor) and correct it they did to 15% faster speed than I was paying for.Correct, paying for 100, testing at 80. Currently paying for gigabit, let's test it...
EDIT: 846.83 and 5, er, jumped to 36.15 upload at the end. It seems Comcast gives me 80% of what I pay for
Fast forward another month and Spectrum raised their min speed now I get 235 Mbps on my 200 Mbps service, consistently.
If you can confirm your only getting 846 you can fill out a complaint and expect a call from your provider in 5 business days or less.