DSGRID and DataStream request differences

I'm currently working on a python model that extracts and processes company data that is largely based on a pre-existing model in excel I received from a colleague. One part of this model uses a function:

@Thomson.Reuters.AFOSpreadSheetFormulas.DSGRID(...)

To my understanding this translates to a Datastream call using DSWS in python looking something like this:

import DataStreamPy as dsws
ds=dsws.DataStream(***credentials***)
data = ds.get_data(...)

This has been working fine in the time I've been using it, but recently I've bounced on a problem where calls to the service in python have stopped working. After consulting the DataStream test REST service it mentions I've reached my monthly download limit. However, the DSGRID function in excel remains functional. Although these two functions seemingly use the same backbone (to my knowledge), one has stopped working while the other proceeds without fail. The image below shows what kind of an error this throws in python.

Can anyone tell me why, how to solve this, or what I'm might be doing wrong in this situation?

Thanks!