fix and sort conference link

service.md

@@ -106,6 +106,7 @@ services listed above, 6 have an unknown state because the
 documentation is external (marked with `?`). Of the remaining 14
 services, it is estimated that 38% of the documentation is complete.
 
+[BBB]: howto/conference
 [blog]: service/blog
 [btcpayserver]: service/BTCpayserver
 [check]: https://gitlab.torproject.org/tpo/metrics/team/-/wikis/Survival-Guides/Check
@@ -127,7 +128,6 @@ services, it is estimated that 38% of the documentation is complete.
 [survey]: service/survey
 [svn]: howto/svn
 [website]: https://gitlab.torproject.org/tpo/web/tpo/-/wikis/home
-[BBB]: https://gitlab.torproject.org/tpo/tpa/team/-/wikis/howto/conference
 
 ## Undocumented service list