This was happening to my Gitlab instance. What happens is that the Bitnami stack reconfigures your settings (in my case, an LDAP setting) to be the same IP address as the server. If you’re finding that your settings aren’t being saved, in particular, anything related to hostnames or IP addresses, just rename the bnconfig executable to something else. The bnconfig file is usually located in the root folder of the stack; for example, for Gitlab, it was /opt/bitnami/apps/gitlab.