Invalid IP Address - DHCP Issue

Would like to start this by noting that my entire description was erased after trying to add a tag to the post. Please fix this so others don’t have to retype their posts when they’re already frustrated and desperate enough to seek help here in the first place. 

Anyway- After temporarily downgrading our wifi speed over a month ago, only my desktop pc (running Windows 10 with an Intel wifi card) will not reliably connect to the wifi network. While it will connect at surface level, I constantly get the error that there isn’t a valid IP configuration. When I pull my IP, it’s a 169.xxx number which is problematic.

I have gone through various websites and forums resetting every possible thing in my computer to try to resolve the issue and have had no success. The chat bot is useless and even after having a technician out to fix the issue, it only resolved the connection for less than 24 hours. I replaced the wifi card in my pc today in case that was the issue but I am still having the exact same error, so it is obviously an XFinity issue.

After jumping through hoops to try to speak with a real human to help with this issue, this is my last resort. Can a real agent PLEASE offer some kind of help? I am happy to offer any additional information needed, but this has impeded my ability to do both work and leisurely activities on my computer for over a month so I need help ASAP.