# X_REPLICATOR_SLOT_HELD

## Means

another replicator already owns this database

## Typical cause

`x dev --role replicator` started while another process holds the database's replicator lock (a container that loses the lock stays up unready and takes over when it frees, so it never throws this) — nothing is wrong with this process, the database already has its one replicator

## Fix

`x dev --role replicator   # rerun after the replicator already on this DATABASE_URL stops — one database has one replicator`

[Realtime](/error-codes#realtime)