[Shahriar]

Go to ../wp-content/plugins/pricing-table/table-templates/rtd-gray/price_table.php and remove following code from bottom of the file

<div style="clear: both;"></div>

If you want to add margin at bottom of table add it here ../wp-content/plugins/pricing-table/table-templates/rtd-gray/css/style.css as following,

#shaon-pricing-table .plan{
margin-bottom:50px;
}

Send login info in private reply if you need help in doing that.

Thanks.