Application and Key limits
One Application per Organization unless it is a Partner Organization, two active keys per Application.
Two limits keep the number of Applications and API Keys small, because each API Key gets the full Quota of its Application.
Application Limit
An Organization can have one Application, suspended ones included. A Partner Organization has no limit. FIVB decides which Organizations are Partner Organizations: once the limit is reached, the Applications page shows a contact link to ask for more Applications.
If your Organization stops being a Partner Organization, it keeps its Applications, but cannot create more while it is over the limit.
Key Limit
An Application can have two active API Keys. Revoked keys do not count. Two keys let you replace one without downtime: see Authenticate with an API Key.
Suspended Applications
FIVB can suspend an Application. While it is suspended, its API Keys do not work (the gateway answers 401 invalid_api_key), and it gets no new key or secret. You can still revoke its keys. The Application page shows that it is suspended. When FIVB reactivates it, its active keys work again, with the same secrets.