Problem to export report


Hello, i created a new report that in his API method recieve a parameter extra, further to the others (idSite, date…). The report works OK, but when I try to export it, shows an error : Please, specify a value for “myParameterExtra”.

I call the report from ajax, and pass the parameter with GET and it works, but i don’t understand why shows that error when I try to export it.

I appreciate if someone can work out the question , Thanks .