restore postgres BBDD - message "already exists"
use
-c
--clean


Output commands to clean (drop) database objects prior to outputting the commands for creating them. (Unless --if-exists is also specified, restore might generate some harmless error messages, if any objects were not present in the destination database.)


This option is only meaningful for the plain-text format. For the archive formats, you can specify the option when you call pg_restore.

see manual
so that all elemenst are dropped before you restore the database.
in your case use pg_restore with the same parameter, that has the same effect