Issue with PUT/user

I have made an endpoint on Xano that edits user details, and I'm using it to update user info while new users are onboarding.
I'm experiencing a weird issue with token authentication.

**Premise
**My Sign up works correctly and I've defined the generated token as "authtoken".
My Sign in works only on test mode from the Bravo studio endpoint collection. If I try to Sign in from the mobile app, it works when the action button is set to open another screen but it gives an error if I set it to "Set Access Token".

Now, my endpoint works perfectly on Xano, it allows to input some fields I need to edit about the user, doesn't require any field, it only requires an auth token since is an authenticated request.
On the Bravo collection looks like this:

1. Headers: Authorization = Bearer ${authtoken}.

2. Test value: authtoken = ++a certain token I take from Xano when I need to test the endpoint from there+++
   (I also tried to change authtoken with "_authorization" still not working

errors I get:
ERROR_CODE_UNAUTHORIZED
Unsupported input

or I get

Duplicate record detected. Please check your input and try again