Hi,
I don't know why the client failed in reconnecting. Possibly a firewall or a change of the server's IP address. I did not try to read fifteen thousand lines of logs (in the future DON'T DO THAT, pick a sample and post something a bit more considerate of the people who are trying to help. Downloading is not a problem for me now with good gigabit fiber, but I used to try to help people on slow ADSL or limited cellular 4G. Taking the time to read it all, though, is definitely a problem.)
Manually switching it off and on would cause the DNS resolution to happen again. That could be an explanation. And it would be something nordvpn might have been able to tell you.
A
forum search for your error seems to suggest these are related to firewall blockage, which again, could also be explained by a change of the server IP address. Or it could be that nordvpn blocks you after a certain time of staying connected. Also something nordvpn might have been able to tell you.
They might also be able to access their server logs, if you talk to them directly, and not their user community. I am not able.
regards, rob0