Lets encrypt problem?

When starting homeassistant lets encrypt is listed as stopped. When trying to start it the button just turns red and it wont start. The supervisor logs say this:
[hassio.dock] Can’t start addon_core_letsencrypt -> 500 Server Error: Internal Server Error (“driver failed programming external connectivity on endpoint addon_core_letsencrypt ([removed}): Error starting userland proxy: listen tcp 0.0.0.0:443: bind: address already in use”)

Can still log in via https: but for how long? anyone know what it measn?