Re: Error Code 1066
That error code is connectivity related. Are you playing on a wired or WiFi connection?
Try logging into your router's admin panel and see if there is an update for your firmware. That's actually helped improve connectivity for others in games like Apex Legends. It's possible you might need to make a quick adjustment to your internet protocol version. In your router's admin panel, try switching to IPv6 if it's available. If you're on IPv6, try switching to IPv4 to see if that has any positive effect.
Sounds pretty frustrating what you're going through since it looks like you've tried many ways to get passed that error.
This was a random solution that worked for Apex Legends players that can help across all games. At this point it's likely something "thing" causing it we have to try and locate.
Killer Control Center
https://answers.ea.com/t5/Bug-Reports/Apex-Legends-random-Freezing-rubber-band-lag/m-p/7435194#M195
Please attach a DxDiag when you have a chance.
https://help.ea.com/en-us/help/pc/how-to-gather-dxdiag-information/
Keep us updated and may the Force be with you.