Cacti Not Graphing

Hi All

I am new to creating graphs in cacti. Following the instructions in the cacti manual I decided to use the template method as this method doesnt require the creation of scripts.

I created a Data Template, then a Graph Template and link the Data Template to the Graph Template. I Then linked the Graph Template to a Host Template.

I added the Host Template to a Device and under the Associated Graph Template the status shows "Is Being Graph" but the Graph is blank.

I have read over the template section in the cacti manual but can see what I am missing.

Hope someone can help.