Uncaught TypeError: Cannot read property 'split' of undefined

Hello,

I am new to ERPNext and I have created a Doctype containing some fields. When I wanted to visualize a report of the 2 record I have there. However, in the chrome/edge console I am getting the error below when I click on submit to create a graph (Bar chart etc.):

report_view.js:448 Uncaught TypeError: Cannot read property ‘split’ of undefined
** at frappe.ui.Dialog.primary_action (report_view.js:448)**
** at HTMLButtonElement. (dialog.js:143)**
** at HTMLButtonElement.dispatch (jquery.min.js:3)**
** at HTMLButtonElement.r.handle (jquery.min.js:3)**

Can someone help please?

Thanks a lot in advance!

any ideas of why this issue is?