Time Series Moving Average not working properly

I have used timeseries in kibana to generate some graphs, however, it seems that it is not generating proper result when I use with moving average.

As from the graph, the index will become 0 afterall, which should be the way how moving average should be presented. Rather than become 0, the line should remain at the point of 5

Is there any problem with the moving average part?

Also, when I try to split chart into separate lines, it could not show proper result.

Is that a limitation of timelion if data is too much?

This link gives you all parameters used in timelion. https://github.com/elastic/timelion/blob/master/FUNCTIONS.md
Maybe it is related to timefield

I have read this but still could not understand what do you mean by it is related to timefield data. How it is affected

In timelion, the field time per default is @timestamp. If you want to do something regarding another time field defined in your log. You have to specify it .
Actually, I had this trouble one time and iwas getting graph like you've got.

But I have already mapped the item with date filter in order to change the @timestamp equals to my timefield.