How to use Bulk Request for the same method multiple times

I am attempting to utilize the Bulk Request method within the API to invoke the same method multiple times, each with a different date parameter. The objective is to gather data for unique visitors over time, enabling the construction of a chart representing the evolution of unique visitors on my application.

Here is an example of how my request is structured:

method=API.getBulkRequest&urls[0]=method%3DVisitsSummary.getUniqueVisitors%26idSite%3D23%26date%3D2023-12-01%26period%3Dweek&urls[1]=method%3DVisitsSummary.getUniqueVisitors%26idSite%3D23%26date%3D2023-12-08%26period%3Dweek&urls[2]=method%3DVisitsSummary.getUniqueVisitors%26idSite%3D23%26date%3D2023-12-15%26period%3Dweek&urls[3]=method%3DVisitsSummary.getUniqueVisitors%26idSite%3D23%26date%3D2023-12-22%26period%3Dweek&urls[4]=method%3DVisitsSummary.getUniqueVisitors%26idSite%3D23%26date%3D2023-12-29%26period%3Dweek

However, in this specific case, I am encountering an issue where I receive the same value five times. Upon further investigation, when I make separate requests for each date, I obtain different values. Strangely, the final value I receive is consistently the value of the last request made. Any insights or suggestions on how to address this behavior would be greatly appreciated.