Your theme is overriding the plugin css for submit button. Add the following CSS code in Custom CSS section of your theme and it will fix the issue for you.
.widget_twb_aw_widget .twb_widget input[type="submit"]{
position: relative;
height: auto;
line-height: inherit;
text-indent: 0;
right: 0;
}
Let me know if still any issue.
thanks