Create Custom subpanel

Hello All,

Not able to create custom sub-panel in contact for aos_invoices.
I am trying below URL:
https://developer.sugarcrm.com/2013/02/27/add-custom-subpanel-in-accounts-module/

using above url i create opportunity subpanel in account module successfully.
but in contact module, custom sub-panel for aos_invoices not created.
my suite Version 7.8.3

Please help me out.
Thank You

Check your php_errors.log to see if it’s throwing an error (missing file, etc.).

If not, you need to give a lot more detail here to get help… exactly what file you used, exactly where you saved it, etc.