I also modified the admin secret (with the RPC credential), and I have a response !!
{“key_id”:“570b59228352270ae5000001cb526aabffaa482e7509a7e39186f34e”}
HOURRA!!!
I can go on with the Tyk2.0 evaluation but I’d like to say that your reactivity and your help can have 6/5 stars 
I wonder what could be the “enterprise” support of Tyk
Thank you for your support and your time.
Fred