DNS errors

Hello. Xfinity worked on my street today “upgrading lines”. Since completion my laptop can only access a few websites. The home page on my televisions won’t load. I can get Disney to woe for example but not Netflix and Hulu. I chatted in, I’ve rebooted my modem. Unplugged the tvs. Etc. They want me to schedule a tech but issue was clearly caused by whatever work was done today. Is there some way I can deal with this myself?