Anyone here integrating forms with Marketo?

I have an Unbounce landing page form integrated with a Marketo List. I wanted to add an additional checkbox field to the form that would sync to a Marketo Boolean (True/False) field. I added the checkbox to the form, and in the Unbounce Integration Settings I synced the Marketo field to the form field. However, each time I try using the form, there is an integration error (“Invalid value for field ____”).

I think the problem could be that in Unbounce the form field (checkbox ) is a string field, while in Marketo it’s a Boolean (True/False) field.

Thanks!