successful validated captcha in session not deleted

[tomg65]

Hi

The environment has a session.
An user commits a contact form with captcha.
Captcha is valid (controller based) and will be deleted in database but not in the session.
If the user calls the contact form again, then the captcha image ist not shown.
The captcha key is still stored in the session but no longer in the database - so the image code in the form is wrong.

Edit:
This happens just in production environment
In production the captcha code will not be new generated.
The method ViewHelper::show_simple_captcha is not called again.
In Middleware::call -> Middleware::make_image -> Utils::simple_captcha_value(code) the SELECT Satement don't get a result and the captcha image is empty

Regards
Thomas