Common error resolution: How do I fix DETAIL: Key (id)=(123) already exists?

This depends on the situation, but you can always try the following yourself first:

# Note: dsmr_sqlsequencereset is only available in DSMR-reader v3.3 and higher
sudo su - dsmr
./manage.py dsmr_sqlsequencereset

See also

If it does not resolve your issue, ask for support on GitHub (see end of page).