Posting here as i cannot find a support contact for Horizon.
The Forge deployment service is awesome however from my experience it seems not reliable with Horizon.
25% of time, deployment through Forge, Horizon is stopped without being restarted.
(In fact in Forge dashboard, checking daemon status, we can read 'RUNNING pid 18922, uptime 0:05:19' but when checking Horizon dashboard we can see it is in fact stopped)
It is necessary then to manually restart the Horizon daemon of server.