checkbox mode doesn't work

I have a list with 3 elements. One of these is a databasejoin plug-in type. In the options I want to use, like "Render join as", checkbox. Everything works but when I submit no data is stored in the list, while if I use for example (like "Render join as") "multi select dropdown" all data are stored. I'd like to use checkbox to select the data because is more simple. Do you have an advice to solve my problem please?
 
We are in need of some funding.
More details.

Thank you.

Members online

No members online now.
Back
Top