ORA-28547: connection to server failed, probable Oracle Net admin error but works after reboot

I get the above error every so often when attempting to connect to oracle (12.1.2) using sqlplus (but sqldeveloper does the same). This tends to happen when the client machine I'm using has been up for a long time:

sqlplus USER/PASSWORD@DBNAME

ORA-28547: connection to server failed, probable Oracle Net admin error

Note: DBNAME is the TNS alias

TNS:

DBNAME=
        (DESCRIPTION=
                (ADDRESS=(PROTOCOL=tcp)(HOST=database.address.com)(PORT=1544)                                                                                                                     )
            (CONNECT_DATA=
                (SERVICE_NAME=DBNAME)
                (INSTANCE_NAME=DBNAME)
            )
        )

The strange thing is if I then reboot to the client machine, the connection works fine again! Anyone know what could be causing this? I'd rather not have to reboot daily!