Thanks for your prompt reply.
I found the culprit! It was the settings in the contacts.
Components-->Contacts-->Parameters was set to Custom Reply
Yes. What actually takes care that another plugin is sending the mail and not joomla. What resulted in my case that nor iJocomment couldn't notify user nor my contact forms worked anymore.
The funny thing is I didn't even remember changing the settings. And even more confusing Community builder notification emails were working ok.
I thought I might be helpful for someone with the same problem. iJocomment uses the same engine the contact forms are using or part of it. So if contact forms don't work joomlacomment notification will also not work.
Cheerz,
Zarro