Attachments inside Nintex form 2016 repeater

Hi All 

We are using On premise nintex 2016, i am trying to add the attachment control inside the repeater but it is giving me pop up saying The control cannot be added to the Repeating Section. But in the help document i read that it is supported. is there any setting i have to do ? Please find the error screenshot attached.

Version Details below.

Nintex Forms 2016