Not able to set array in Form

I am using Flowable Designer where I need to set form input field value to something like this: {{root.approvers[loopCounter].reviewComments}} but it is giving error “property.value.title does not match”.
I am trying tutorial chapter 9 of Flowable documentation. Link to tutorial

Could you please help me why it is not binding the form input field value?

I assume you’re talking about Flowable Design? If so the question should be asked here: (this is the open source forum)