Reverse DNS Resolution Not Working After Installing Bind9 in Ubuntu Server

I installed DNS Server (bind9) in my ubuntu server and I am able to do name resolution from hostname to ip address using nslooup and dig; however when I try to do reverse lookups I get an error nslookup 192.168.137.5 ** server can't find 5.137.168.192.in-addr.arpa: NXDOMAIN that ip address is the ip address of the local server which is also the nameserver with bind9 installed. if I do forward lookups works just fine nslookup example.com Server: 192.168.137.5 Address: 192.168.137.5#53 Name: example.com Address: 192.168.137.5 Name: example.com Address: ::1 Here are my configuration files 3 in total: named.config.local, forward.example.com, reverse.example.com named.conf.local zone "example.com" IN { type master; file "/etc/bind/forward.example.com"; }; zone "137.168.192.in-addr.arpa" IN { type master; file "/etc/bind/reverse.example.com"; }; forward.example.com $TTL 604800 @ IN SOA example.com. root.example.com. ( 2 ; Serial 604800 ; Refresh 86400 ; Retry 2419200 ; Expire 604800 ) ; Negative Cache TTL ; @ IN NS home-server.example.com. @ IN A 192.168.137.5 @ IN AAAA ::1 home-server IN A 192.168.137.5 wintop IN A 192.168.137.1 reverse.example.com $TTL 604800 @ IN SOA example.com. root.example.com. ( 2 ; Serial 604800 ; Refresh 86400 ; Retry 2419200 ; Expire 604800 ) ; Negative Cache TTL ; @ IN NS home-server. @ IN PTR example.com. @ IN AAAA ::1 home-server IN A 192.168.137.5 host IN A 192.168.137.5 wintop IN A 192.168.137.1 10 IN PTR home-server.example.com. 11 IN PTR wintop.example.com.