remove nulls from count qlik sense

[joeybird]

hi

on a table chart on qliksense I have the dimension CustomerID

I have the following expression measure on a table

if(COUNT(distinct{$<MonthChart= {"$(='>=' & MonthStart(AddMonths(Max(MonthChart),-2)) & '<=' & AddMonths(Max(EventDate),-0, 'DD/MM/YYYY'))"}>}orderid)>=4,

COUNT(distinct{$<MonthChart= {"$(='>=' & MonthStart(AddMonths(Max(MonthChart),-2)) & '<=' & AddMonths(Max(EventDate),-0, 'DD/MM/YYYY'))"}>}orderid))

This is counting correctly. However I want to remove the nulls counts against the other Customer IDs. I have tried unchecking the show nulls values box, and still no joy. please help

is there another way of count if any customer has made 4 or more orders in the last 3 months (from a month chosen)? to prevent the nulls