getting error while accessing Invoice...

Hi all,
payable manager (responsibility) --> invoices --> entry --> invoices

I am getting below error:

"function not avilable to this responsibility.Change responsibilities or contact your system administrator"

And also when i am trying to access 

payable manager (responsibility) --> invoices --> inquiry --> invoices....the form just hangs.

Please share with me if anyone come across with this issue...

Thanks,

Jay