Hi,
Im NOT Author of this plugin nor part of the staff but if you are using sidebar widget option you could try instead of ready widget use text widget (HTML) paste this code and fill your content
[smlsubform prepend=”???” showname=true nametxt=”???” nameholder=”???” emailtxt=”” emailholder=”???” showsubmit=true submittxt=”???” jsthanks=false thankyou=”???”]
let me know if it helps
