Error while using a variable for join time out

we are using a variable which will have the time out value for joins expressed in milli seconds.
When I try it in my development environment its working properly and the step times out in specified time.
When I move the code to testing env I get the following error.

[PRT.0101.9322] Pipeline timeout variable “TimeOut” does not exist in the pipeline.

The variable name that I have used is TimeOut – can this be used as the variable name or is it better to change it.

I am actually setting this variable in the first step’s flow service but when I check in the second step’s input I dont see the value.
The input list of the second step has this variable also.

Any suggestions on how to debug this will be really helpful.

Environment : wM 7.1.2