Unable to deny remote access to Postgresql even if there is no entry in pg_hba.conf
The IP address should be followed by either a slash and a mask length (like /32) with no whitespace, or by whitespace and a netmask (like 255.255.255.255).  What you seem to have here is whitespace and mask length.  So you get a mask length being interpreted as a netmask.  I am surprised that that doesn't throw an error upon parsing, but in any event it doesn't do what you want.