Getting 502 Bad Gateway after attempting upgrade

[Canapin (Coin-coin le Canapin)]

You’re hitting a rate limit from Docker.

Many users were able to resolve the issue by disabling IPv6.

https://github.com/docker/hub-feedback/issues/2421

Similar issue:

Docker Rate Limit Error on Launcher Rebuild

Turning off IPv6 on the Digital Ocean server solved the issue: Here is instruction from DO on how to turn off IPv6.