Hello @iftekhirul!

Thank you for your question.

There is a new feature in that you have to double click in the text area to edit. It will no longer appear on the left side. 
 

Hope that helps!

Thank you for being part of the community.

Alexandra :) 

Welcome to the community @iftekhirul 

The first screenshot is showing a Klaviyo update that rolled-out recently. You now edit the content within the text block itself by double clicking it. There is no longer a seperate visual editor panel on the left, though the HTML source code editor is still there.

Looks like one of your accounts has the new look and the other does not.

Regards

Andy