You can edit directly the bpmn and define only one content so you don't have two inputs with the same name:
<dataInputAssociation>
<sourceRef>content</sourceRef>
<targetRef>_17_ContentInput</targetRef>
</dataInputAssociation>
Or the other option, simpler, is to leave Content empty, and define another variable name (in Parameter Mapping) for your content. If Content is empty, the input our your task will be all the parameters you define.
Demian