SMS notification errorafter upgrade to 6.5 version
I posted a Issue with what I found: https://github.com/traccar/traccar/issues/5413
The issue is fixed on master. The easiest workaround for now is to remove the line break from template files:
https://github.com/traccar/traccar/commit/f53d4c24cd7cc4b7cbd3bd043f8d1e95c72d24e4
What does the configuration look like?