Its probably as issue with your assign token activity. It looks like your not updating or assigning anything to the batchtotal token.

Thanks for the reply Xavier, 

In the assign token activity I have

Action: Modify Value
Activity: Make token for total
Token: BatchTotal

New Value: %(TokenCalculator_next_total)

The bug is in your token calculator token, its never being assigned a value. Check the token values are numbers and not strings and

ok this is the exact string I have

%(RetrieveFieldValues_Amount Payable)+ %(Total)

I marked Total as a number and the token calculator next_total is also checked as a number

should I be doing something different in there ?

I don't see a "Total" token in your screenshots above, just "BatchTotal", so it looks like a typo maybe?

The following workflow works for me:

Thanks Miruna. seems so simple. The issue seems to be that the variables aren't holding the value. so I am looking into the template field type. It's the amounts payable field which in my template is

type:number
no constraints
format: custom  0.00

The strange thing is when I track the token, when BatchTotal is created is has the default 0. But after the first entry the BatchTotal is empty. 

NextTotal is always empty, track tokens doesn't show anything there in any iteration

This is the error.  is this a data entry error in the fields ?  when I output just that field.. it shows the values or when I track tokens.. it has the amount in the CurrentEntry var

Any chance that this workflow is a business process?

yes it is, omg I turned off business process and it worked..

ok please help me understand :) thanks