blocked me out from my own site

I liked this plugin.But I have an problem with this plugin.It has a login screen bug.I saw that if I put wrong information while login it shows no error but a blank div.So I started to experiment with deactivating plugins one by one and check with wrong login information.But iThemes Security plugin locked me out of my site due to too many bad login attempts.I went to my cpanel and delete iThemes Security plugin and I saw that login screen’s bug was fixed.iThemes Security plugin was responsible for this.Please fix this problem. ??