I Signed up today and everything was fine. When my session expired and tried to sign back in, it didnt recognized it. I tried the following and failed

-Turned off Mozilla VPN
-Add Delta.com to Internet Options
-Reboot
-Try in Firefox's Private Browser
-Remove AdBlockPlus
-Cleared Firefox's Cookies

What did work was popping a Virtual Machine and logging in on Edge on the VM. Seems to be a problem with my computer.

Best Buy is also encountering a similar issue where i tried to make a purchase and when i put my information, it gives me "network error"