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Please follow the steps below to properly pass in the custom field(s):
Take the custom field name from custom field section of the campaign and replace all spaces with underscores
Prefix the field name with the string "custom_"
Add the resulting string to the parameter list
(EXAMPLES) *Case sensitive
"Pets Name" --> "custom_Pets_Name"
"Drivers License Number" --> "custom_Drivers_License_Number"
"hobbies" --> "custom_hobbies"
Step 5: Duplicating Custom Fields
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