Getting cached version of document when exporting to file

Hi,

I'm using the BO rest api to refresh a document's parameters and then export it to a pdf.

The documents has a number of parameters (not all of the mandatory) - e.g.

param_1 (mandatory)

param_2 (mandatory)

param_3 (optional - depends on param_1 & param_2)

When I set all three params the export works fine (the data I get correspond to the params I set). The problem is that when I set the first two params, the export is all wrong (probably a cached version). Any ideas what could go wrong?

Thanks.