Did you already ask yourself if all IP addresses can be geolocalized? the short answer is no but do you know what are reserved IP blocks and why? here are some explanations.
When the Internet IP address space was architecture, the Internet Engineering Task Force (IETF) and the Internet Assigned Numbers Authority (IANIA) have reserved several ranges of IP addresses for special uses and purposes. There exist reserved IP intervals with IPv4 and IPv6.
All IP addresses and range mentioned below do not make sense in a geolocation context and as such, it explains why you won't get information when you search for information with such an IP address on an IP geolocation service.
IPv4
0.0.0.0/8 (from 0.0.0.0 to 0.255.255.255)
Addresses in this block refer to source hosts on "this" network. Address 0.0.0.0/32 may be used as a source address for this host on this network; other addresses within 0.0.0.0/8 may be used to refer to specified hosts on this network.
10.0.0.0/8 (from 10.0.0.0 to 10.255.255.255)
This block is used for communications within a private networks. Addresses from this block are commonly used for local area networks (LANs) in residential, office, and enterprise environments. Addresses within this block do not legitimately appear on the public Internet. The addresses can be used without any coordination with IANA or an Internet registry. Similar to 172.16.0.0/12 and 192.168.0.0/16.
100.64.0.0/10 (100.64.0.0 to 100.127.255.255)
This block of about 4 million addresses is a shared address space for communications between an Internet Service Provider (ISP) and its subscribers when using a Carrier-Grade NAT (CGN). The range was assigned by IANA to ensure proper working of carrier-grade NAT (CGN) and alleviating the demand for the last remaining IPv4 addresses. Instead of using unique addresses from the rapidly depleting pool of available globally unique IPv4 addresses, ISPs use addresses in 100.64.0.0/10 for this purpose. Because the network between CPEs and the ISP's routers is private to each ISP, all ISPs may share this block of addresses.
127.0.0.0/8 (from 127.0.0.0 to 127.255.255.255)
Loopback addresses: Each packet sent to one of these addresses is sent back internally instead of leaving the host.The address 127.0.0.1 is the standard address for IPv4 loopback traffic. Although the rest are not supported by all operating systems, they can be used to set up multiple server applications on the same host, all listening on the same port number.
169.254.0.0/16 (from 169.254.0.0 to 169.254.255.255)
Addresses for automatic configuration (APIPA, DHCP, Zeroconf). They are used for link-local addresses between two hosts on a single link when no IP address is otherwise specified. These addresses should only occur within this network.
172.16.0.0/12 (from 172.16.0.0 to 172.31.255.255)
Addresses for private networks; address need not be registered for use. They may not, however, be used on the public internet. Similar to 10.0.0.0/8 and 192.168.0.0/16.
192.0.0.0/24 (from 192.0.0.0 to 192.0.0.255)
The IETF has reserved the address block for use for special purposes relating to protocol assignments.
192.0.2.0/24 (from 192.0.2.0 to 192.0.2.255)
Assigned as TEST-NET-1 and reserved for use in documentation and examples. It is often used in conjunction with domain names example.com or example.net in vendor and protocol documentation.
192.88.99.0/24 (from 192.88.99.0 to 192.88.99.255)
Formerly used for IPv6 to IPv4 relay (included IPv6 address block 2002::/16).
192.168.0.0/16 (from 192.168.0.0 to 192.168.255.255)
Used for local communications within a private network. These addresses need not be registered for use. They may not, however, be used on the public internet. Similar to 10.0.0.0/8 and 172.16.0.0/12.
198.18.0.0/15 (from 198.18.0.0 to 198.19.255.255)
Used for benchmark testing of inter-network communications between two separate subnets. This range was assigned to minimize the chance of conflict in case a testing device were to be accidentally connected to part of the Internet. Packets with source addresses from this range are not meant to be forwarded across the Internet.
198.51.100.0/24 (from 198.51.100.0 to 198.51.100.255)
Assigned as TEST-NET-2 and reserved for use in documentation and examples. It is often used in conjunction with domain names example.com or example.net in vendor and protocol documentation.
203.0.113.0/24 (from 203.0.113.0 to 203.0.113.255)
Assigned as TEST-NET-3 and reserved for use in documentation and examples. It is often used in conjunction with domain names example.com or example.net in vendor and protocol documentation.
224.0.0.0/4 (from 224.0.0.0 to 239.255.255.255)
In use for IP multicast (broadcasting of data from one sender to a select group of recipients), formerly known as the Class D address space.
240.0.0.0/4 (from 240.0.0.0 to 255.255.255.254)
This block, formerly known as the Class E address space, is reserved for future use.
255.255.255.255/32 (255.255.255.255 only)
Reserved for the "limited broadcast" destination address.
IPv6
::/0 (from :: to ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
Default route.
::1/128 (from ::1 to ::1)
Loopback address to the local host.
::ffff:0:0/96 (from ::ffff:0.0.0.0 to ::ffff:255.255.255.255)
IPv4 mapped addresses.
64:ff9b::/96 (from 64:ff9b::0.0.0.0 to 64:ff9b::255.255.255.255)
IPv4/IPv6 translation.
64:ff9b:1::/48 (from 64:ff9b:1:0:0:0:0:0 to 64:ff9b:1:ffff:ffff:ffff:ffff:ffff)
IPv4/IPv6 translation.
100::/64 (from 100:: to 100::ffff:ffff:ffff:ffff)
Discard-Only Address Block
2001::/23 (from 2001:0:0:0:0:0:0:0 to 2001:1ff:ffff:ffff:ffff:ffff:ffff:ffff)
IETF Protocol Assignments.
2001::/32 (from 2001:: to 2001::ffff:ffff:ffff:ffff:ffff:ffff)
Reserved for Teredo tunneling. Teredo is a transition technology that gives full IPv6 connectivity for IPv6-capable hosts that are on the IPv4 Internet but have no native connection to an IPv6 network. Unlike similar protocols such as 6to4, it can perform its function even from behind network address translation (NAT) devices such as home routers.
2001:1::1/128 (2001:1::1 only)
Anycast address reserved for the Port Control Protocol (PCP) protocol.
2001:1::2/128 (2001:1::2 only)
Traversal Using Relays around NAT Anycast
2001:2::/48 (from 2001:2:0:0:0:0:0:0 to 2001:2:0:ffff:ffff:ffff:ffff:ffff)
Benchmarking
2001:3::/32 (from 2001:3:0:0:0:0:0:0 to 2001:3:ffff:ffff:ffff:ffff:ffff:ffff)
AMT
2001:4:112::/48 (from 2001:4:112:0:0:0:0:0 to 2001:4:112:ffff:ffff:ffff:ffff:ffff)
AS112-v6
2001:20::/28 (from 2001:20:: to 2001:2f:ffff:ffff:ffff:ffff:ffff:ffff)
Reserved for Overlay Routable Cryptographic Hash Identifiers (ORCHID) v2.
2001:db8::/32(from 2001:db8:: to 2001:db8:ffff:ffff:ffff:ffff:ffff:ffff)
Addresses used in documentation and example source code.
2002::/16 (from 2002:: to 2002:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
The 6to4 addressing scheme (it is now deprecated)
2620:4f:8000::/48 (from 2620:4f:8000:0:0:0:0:0 to 2620:4f:8000:ffff:ffff:ffff:ffff:ffff)
Direct Delegation AS112 Service
fc00::/7 (from fc00:: to fdff:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
Unique local address.
fe80::/10 (from fe80:: to febf:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
Link-local address.
ff00::/8 (from ff00:: to ffff:ffff:ffff:ffff:ffff:ffff:ffff:ffff)
Multicast address.