Hi,
There is a known issue with Azure Portal where some of the services are not listed with certain Subscriptions and the issue is intermittent.
If you still see the problem I suggest you contact the Azure Support team and let them know about this issue.
Or you can try refreshing the browser, clearing the browser cache, try another browser, or wait a while and the problem should be resolved.
(Please don't forget to accept helpful replies as answer)
Best regards,
Leon