Calculated timeseries stopped working

I have a calculation on a chart that was working well for quite a while, Then there was a network issue that stopped the data source from streaming data (this is the big triangular shape in the image below). Even though the data streaming got restored a short while after that, the issue I have is that the calculated value (the brown line) never got back to working. There was a short blip of time where it looked like it was working but that was just random values for a while. 
Does anyone know where I can see any logs associated with this calculation? I know you can’t edit the calculation - you have to delete it and create a new one - I guess I will likely do that but would also like to find out what the reason is for this calculation just stopping and not restarting properly?