fix(ins): fix typo

Author: bene2k1

pages/instances/troubleshooting/fix-unreachable-ipv6-rhel-based-instance.mdx

@@ -24,9 +24,16 @@ The affected O/S distributions are:
 - AlmaLinux versions 8 and 9
 - Fedora versions 37 and 38.
 
+<Message type="note">
+  CentOS 7.9 is not concerned by this issue as it does not support routed IP.
+</Message>
+
+This guide addresses specific issues related to RHEL-based Instances after transitioning to routed IP.
+For general information on routed IPs and migration procedures, refer to our [main migration guide](/instances/how-to/migrate-routed-ips/) and the [related FAQ](/faq/instances/#are-there-any-limitations-on-ip-autoconfiguration-with-the-routed-ip-feature).
+
 ## Cause
 
-CentOS 7.9 is not concerned by this issue as it does not support routed IP. This guide addresses specific issues related to RHEL-based Instances after transitioning to routed IP. For general information on routed IPs and migration procedures, refer to our [main migration guide](/instances/how-to/migrate-routed-ips/) and the [related FAQ](/faq/instances/#are-there-any-limitations-on-ip-autoconfiguration-with-the-routed-ip-feature).
+This issue is caused by a missing NetworkManager configuration for IPv6 address generation mode (`ipv6.addr-gen-mode=0`) on RHEL-based instances.
 
 ## Possible solution