Note to self: https://github.com/Vaskivskyi/ha-asusrouter/issues/993
If you can connect to the container, run pip show asusrouter and confirm that somehow it is not of version 1.21.0
pip show asusrouter
If you can connect to the container, try installing the dependency manually with pip install asusrouter==1.21.0. If you get any errors, post them here, please. Package installation issues might be related to the other custom integrations and their dependencies.
pip install asusrouter==1.21.0