Can't update to 6.18

Troubleshooting
1

I’m using a rock64 and getting this error and also one earlier about dietpi.txt:

Err:1 https://deb.debian.org/debian-security stretch/updates InRelease
  Failed to connect to deb.debian.org port 443: Connection timed out
Err:2 https://download.mono-project.com/repo/debian stretch InRelease
  Connection timed out after 120000 milliseconds
Err:3 http://dev2day.de/pms stretch InRelease
  Could not connect to dev2day.de:80 (144.76.172.47), connection timed out
Err:4 http://deb.ayufan.eu/orgs/ayufan-rock64/releases  InRelease
  Could not connect to deb.ayufan.eu:80 (51.15.234.190), connection timed out
2

Which version is your DietPi currently?
Looks like your internet connection is down? Can you ping external sides? E.g.: ping dietpi.com