Go To Edit Html > Expand Widgets
Search for below codes:
<b:includable id='status-message'>
<b:if cond='data:navMessage'>
<div class='status-msg-wrap'>
<div class='status-msg-body'>
<data:navMessage/>
</div>
<div class='status-msg-border'>
<div class='status-msg-bg'>
<div class='status-msg-hidden'><data:navMessage/></div>
</div>
</div>
</div>
<div style='clear: both;'/>
</b:if>
</b:includable>
And now replace above codes with below :-
<b:includable id='status-message'>
<b:if cond='data:navMessage'>
<div>
</div>
<div style='clear: both;'/>
</b:if>
</b:includable>
Just done . Now save it. You have Done.