Clean system, no packages installed, empty /var/db/ports.

cd /usr/ports/databases/py-sqlalchemy14
make config-recursive

This causes the following error:

===> Setting user-specified options for py311-sqlalchemy14-1.4.54 and dependencies
===> Building/installing portconfig as it is required for the config dialog
===>  Cleaning for portconfig-0.6.2_2
===>  Cleaning for portconfig-0.6.2_2
===>  portconfig-0.6.2_2 FLAVOR is defined (to py311) while this port does
not have FLAVORS.
*** Error code 1

Stop.
make[3]: stopped in /usr/ports/ports-mgmt/portconfig

===> Options unchanged
===> Building/installing portconfig as it is required for the config dialog
===>  Cleaning for portconfig-0.6.2_2
===>  Cleaning for portconfig-0.6.2_2
===>  portconfig-0.6.2_2 FLAVOR is defined (to py311) while this port does
not have FLAVORS.
*** Error code 1

Stop.
make[3]: stopped in /usr/ports/ports-mgmt/portconfig

===> Options unchanged

E.g. there are port knobs for py-sqlalchemy14, it defaults to py311 FLAVOR, needs to build portconfig, however the FLAVOR is passed along and portconfig fails to build.

This is probably ports build system error not an error of portconfig port.

I have been bitten with this multiple times in the past, previously with dialog4ports:

2020-10-15 dialog4ports-0.1.6 FLAVOR is defined (to py37) while this port does not have FLAVORS.
2021-11-12 dialog4ports-0.1.6_1 FLAVOR is defined (to py38) while this port does not have FLAVORS.
2023-06-19 dialog4ports-0.1.6_1 FLAVOR is defined (to py39) while this port does not have FLAVORS.

The workaround was to first install dialog4ports/portconfig manually.