Introspect token return false after first time

Hi,
I’m new with keycloack, i have some issue when i try to introspect my token.
I followed the documentation looking for the api that validates my token, after calling the introspect api the first time, the service return active but for the following times the token, even if valid, always returns false? How can I solve the problem? I have a baseline configuration, I’ve created my own realm, added a user and created a client, I haven’t made any changes at the realm or client level, my client uses opeid with client and secret. i’m using latest version of keycloack.

Thank you,
Best regards.