Display a error log line although logout response is success

[oNguyenThiThuy]

I implement logout function like this:
when user clicks logout button -> call action destroy on session controller (DELETE "/users/sign_out"), this action will redirect to IdP to clear IdP session. After that, IdP will redirect back to POST "/users/saml/idp_sign_out" with a logout response.

These step is very normal, I do not custom any thing with this gem.

Although user log out successfully, I got a error log in rails console, like this:

Started POST "/users/saml/idp_sign_out" for 127.0.0.1 at 2021-01-21 14:44:01 +0700
Processing by Devise::SamlSessionsController#idp_sign_out as HTML



// something over there
saml: Auth errors: The status code of the Response was not Success
Redirected to //logouted_path
Completed 302 Found in 91ms (ActiveRecord: 0.7ms | Allocations: 32170)

The partial of decoded logout response, that I've got from IdP, is:
<samlp:Status><samlp:StatusCode Value=\"urn:oasis:names:tc:SAML:2.0:status:Success\"/></samlp:Status>

Is there any solution to delete the error log? Thankyou