Hey Amema,

I have tried to access in your Joomla backend, but it keep redirect back to your homepage.

By the way, you have to set 2 place for your default editor setting :
#1. Go to your backend > system > global configuration > Default Editor - JCE
#2. Go to your backend > Easyblog > settings > general > composer > Composer Editor - JCE

Regarding with your JCE editor responsive issue :
>> can you try configure that JCE editor width and height setting from backend > JCE > editor profile > select your profile > features & layout > width and height and see is it can help or not.

If the issue still persists, perhaps you can consult with JCE editor developer regarding and see how it goes.