Slow download speed

Hi, I have been using Xfinity as my internet provider about 4-5 months now. Everything was great up until I started having issues on my Linux Pc. At first I thought it was a driver problem so I installed new drivers however that didn't change anything, then I changed the distro I was using from bazzite to cachyos this didnt work either. Then I tried using a ethernet cable which made it worse. I tried rebooting the modem that didnt work as well. Currently I am having 20 mbps download speed, my plan is 300 mbps. I tested the internet speed on a Windows, I am getting about 300mbps on my windows pc. I dont know what to do anymore is this a problem caused by my pc or xfinity just isnt working well with Linux based OSes. Please help.