You’ve connected correctly, but you need to use the correct database name.
psql -U postgres -h localhost -p 15432 -d your_database < latest.dump
You can find out the name of your databases by connecting locally and listing them with \l
postgres=# \l
List of databases
Name | Owner | Encoding | Collate | Ctype | Access privileges
-----------+------------+----------+------------+------------+-------------------------
--
main | flypgadmin | UTF8 | en_US.utf8 | en_US.utf8 |
postgres | flypgadmin | UTF8 | en_US.utf8 | en_US.utf8 |
template0 | flypgadmin | UTF8 | en_US.utf8 | en_US.utf8 | =c/flypgadmin
+
| | | | | flypgadmin=CTc/flypgadmi
n
template1 | flypgadmin | UTF8 | en_US.utf8 | en_US.utf8 | =c/flypgadmin
+
| | | | | flypgadmin=CTc/flypgadmi
n
(4 rows)