Comment 1 for bug 1669823

It may also be worth mentioning that this is not only observed in Horizon. Here, we can also see "Flavor not found" in the nova show output in the CLI:

root@node-1:~# nova show 0dbba63c-b12a-44de-a409-5b02e7688aa3
+--------------------------------------+----------------------------------------------------------+
| Property | Value |
+--------------------------------------+----------------------------------------------------------+
{truncated}
| description | testInstance |
| flavor | Flavor not found (27278f90-0afc-4fc9-a4b2-138a2b5802a9) |
| hostId | ba6d7e70d29b1d9c27087b96784e6a2912da7d086a2149ce50db1d37 |
| id | 0dbba63c-b12a-44de-a409-5b02e7688aa3 |
| image | TestVM (2d93532f-6285-44ce-b5d1-ee8dab748023) |
{truncated}
+--------------------------------------+----------------------------------------------------------+