Power BI Report builder date format issues

I have a problem with Power bi Report builder, i am using a power bi dataset connection to fetch data..

For any reports I am running it interprets all of my dates as US format. using the Power BI report builder, although the dates appear in the correct format in the report builder app but when uploaded
in a premium workspace, it switches to US format.

parameters are of string type but are passed the likes of

@StartDate = '08/11/2019 12:00:00 AM'
@EndDate = '15/11/2019 12:00:00 AM'

Now I run the report on my developemtn machine, this fetches result from 11/8/2019 to 11/15/2019 - appears to be dd/mm/yyyy but the results are wrong

in the power bi portal, the format changes as below and the results are wrong again.

@StartDate = '11/08/2019 12:00:00 AM'
@EndDate = '11/15/2019 12:00:00 AM'

i have changed the regional settings in my devlopment machine to en-AU.

does anyone have any ideas as to why this is happening?