How I can access to oroPlatform API?

Question

I wanna access to OroPlatform API but unfortunately, I'm still getting message:

{"error":"no_encryption_key","error_description":"The encryption key does not exist.","message":"The encryption key does not exist."}

I have already create oauth_private.key and oauth_public.key in /var forlder. Currenlly in my dashboard I achieved delete the message of contact with the administrator for the key. But still I can request from Posman or another client.

I have tried with all these methods without success:

https://doc.oroinc.com/api/authentication/oauth/#:~:text=Authentication-,OAuth%20Authentication,-Authorization%20Code%20Grant

I'm getting crazy with this issue. Somebody can help me please??