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If the methods need there own variables, give them their own variables but use names for the variables in the method that are different from the class variables.

Make sure that you do NOT give the SAME names to local variables as class variables have. This can be a problem. Give them different names.

Is your problem because you have variables with the same name as class variables inside of methods?
You should rename all the variables used in your methods so they have different names from the...

Can you define the variables at the class level vs inside of the methods?