Incomplete timeseries parameters inside Eikon API

Try

ek.get_data(['Oc1'],['TR.SETTLEMENTPRICE.date', 'TR.SETTLEMENTPRICE'],{'SDate':'2016-03-01', 'EDate':'2017-07-28'})

If you were using Formula Builder wizard in Eikon Excel to discover field names, check out Parameters & Quick Functions tab on the right hand side of the wizard dialog box after you've selected the field. In this tab you will find parameters applicable to the field you've chosen as well as output options. The latter is how you can discover TR.SETTLEMENTPRICE.date to get the dates.

I'm afraid there's no way currently to retrieve this data using Eikon Python API.
Here's the link to a similar question asked on this forum previously.
https://community.developers.refinitiv.com/questions/16910/how-do-i-download-historical-data-from-starmine.html

And here is another example (implemented in R), where dates must be coming out wrong:

fieldify<-function(x){
   return(as.list(paste0(x,c("(SDate=19890101,EDate=0,Curn=NOK,Frq=D).date","(SDate=19890101,EDate=0,Curn=NOK,Frq=D)"))))}

data_frame1<- data.table(get_data(list("B0VKMC4"), fieldify('TR.PriceClose'),debug=F))

data_frame2<- data.table(get_data(list("B0VKMC4"), fieldify('TR.ASKPRICE'),debug=F))

I assume that the TR.PriceClose works correctly, while TR.ASKPRICE does not:

> data_frame1
      Instrument                 Date      Price Close
   1:    B0VKMC4 2005-12-27T00:00:00Z 41.3636146430895
   2:    B0VKMC4 2005-12-28T00:00:00Z 41.2274194311675
   3:    B0VKMC4 2005-12-29T00:00:00Z 41.4107644028658
   4:    B0VKMC4 2005-12-30T00:00:00Z 41.4387631868717
   5:    B0VKMC4 2006-01-02T00:00:00Z 41.2204024211472
  ---                                                 
3030:    B0VKMC4 2017-08-07T00:00:00Z 56.6653645219114
3031:    B0VKMC4 2017-08-08T00:00:00Z 56.7369633667787
3032:    B0VKMC4 2017-08-09T00:00:00Z 56.9109469055681
3033:    B0VKMC4 2017-08-10T00:00:00Z 57.1856936041995
3034:    B0VKMC4 2017-08-11T00:00:00Z 57.0047611167585
> data_frame2
      Instrument                 Date        Ask Price
   1:    B0VKMC4 1989-01-02T00:00:00Z  49.516359760791
   2:    B0VKMC4 1989-01-03T00:00:00Z 41.5984501355687
   3:    B0VKMC4 1989-01-04T00:00:00Z 41.3001324064879
   4:    B0VKMC4 1989-01-05T00:00:00Z 41.2162677012143
   5:    B0VKMC4 1989-01-06T00:00:00Z  40.573643486065
  ---                                                 
7064:    B0VKMC4 2017-08-07T00:00:00Z                 
7065:    B0VKMC4 2017-08-08T00:00:00Z                 
7066:    B0VKMC4 2017-08-09T00:00:00Z                 
7067:    B0VKMC4 2017-08-10T00:00:00Z                 
7068:    B0VKMC4 2017-08-11T00:00:00Z 

Please see the overview page for the API on this Developer Portal.
https://developers.thomsonreuters.com/eikon-web-and-scripting-apis

The API is titled "Eikon Web and Scripting APIs Beta". It is a wide open Beta, which you're welcome to join. But we're not yet offering production support for this API. If you expect production quality, please consider using mature APIs (COM or .NET).

I think it is best not to get too hot under the collar from either end. This product is very promising, while "mature" APIs are of limited usability.

The best way forward is to try and see what is causing issues with get_data output. And in particular, date-data alignment. And how to diagnose it.

Alex, do you have some suggestions?

The best way to deal with data issues is to reproduce them using Eikon Excel and report to Thomson Reuters Helpdesk.