Custom blocks not displayed in settings page after upgrading to OJS3.1.1.2

Hi,
I upgraded our website from OJS 2.4.8 to 3.1.1.2 and the problem is that custom blocks are displayed on website homepage but I can not see them in the settings/appearance page for re-ordering. I tried enabling and disabling the custom block plugin which did not help. I also added a new custom block but even this newly added block is not displayed in settings page.
any ideas?

cheers,

I am still struggling with this issue.
Any ideas?