Mapplet parameter not taking value from Paramter file (Informatica)

I've added a parameter in my Informatica mapplet and I'm passing the value through a parameter file that is being called by the workflow. It reads from the file and at the workflow level, it stores the correct value. But it gets replaced by 'default value' as null at the mapping level and hence the session fails when this null is passed in an expression.

I want to pass 55000 as the value, not null. Following is the session log:-

VAR_27028    Use override value [55000] for user-defined workflow/worklet variable:[$$func_num].

VAR_27027   Use default value [] for mapping parameter:[mplt_test1.$$func_num].

Python 26-07-22, 4:30 p.m. raivivan

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