admin stopped working

Hi,
two days ago i have updated my wp to 6.0.2. Then i installed ithemes security. Yesterday i have tried to add new post – i didnt see categories a got JSON error. I googled it and then delete this plugin. Now i cannot access to my admin page. When i type /wp-admin it shows me white page. When i type /wp-login.php it show login page but after login the same result as wp-admin. I have tried:
– restoring .htaccess
– upload new wp-login.php file
– define WP_HOME nad WP-SITEURL in wp-config.php
– increased php memory limit

I dont have dictionary of that plugin. Can you help me?